Mr. President and Gentlemen :—Not very many years ago, probably quite within the recollection of some of the old officers of the navy, the great ocean storms were very imperfectly understood and marine disasters were frequent and terrible. The attention of several scientific men was attracted to the subject and eventually Mr. William Redfield of New York discovered after long and careful investigation into the matter, that the winds in these storms blew in circles round a center of low pressure, and that the great number of marine disasters were mainly due to ignorance of this fact.
Certain rules for the management of ships in a storm were published and proved a great blessing to seamen, who, by observing these, were enabled to escape the dangerous part of it, either by running away from the center, or by heaving to in time on the proper tack and letting it pass.
Later, however, several other scientists have taken up the subject of storms and by various methods of investigation have arrived at different conclusions. Some of them have gone so far as to say that the circular theory is all wrong, and the rules for navigation based upon it are worse than useless, and the question to-day is : How the winds blow within the storm disk?
It is with this question that I propose to deal this evening, and in doing so will endeavor to confine myself to facts from which every one may draw his own conclusions and judge of the correctness of mine. By way of introduction I will touch briefly upon the history and progress of this, to seamen, all-important subject, and mention only a few of the principal cases that were published in the newspapers and scientific journals of the time, and which doubtless served to call the attention of scientific men to the matter, as also to arouse the spirit of investigation and a desire to clear up the mystery which enveloped the entire subject at that time, by comparing and generalizing observed facts, as reported from time to time by men who had the good fortune to escape with their lives from the terrible storm center, and to come back and tell the tale of the fearful things they had seen.
The first authentic information relating to circular storms (which, for the sake of brevity I will call cyclones) was published in England (Philosophical Transactions, October, 1698) in a paper on the West India hurricanes by Captain Langford, who speaks of the storms as whirl-winds, describes the veering of the wind, and the progressive movement of the whole storm.
The Spanish navigator, Don Juan d'Ulloa, during a cruise on the Pacific coast of South America in the year 1743 experienced several storms in which the wind changed from north to west, (which would occur in the northeast quadrant of a cyclone in the southern hemisphere traveling southward and eastward).
A French writer named Romme, in a work entitled "Tableaux des vents, des marges et des courans" published in 1806, describes storms in the China Sea near the gulf of Tonkin, which he distinctly calls whirlwinds, and applies the same name to other storms experienced in the Mozambique channel, and again others in the gulf of Mexico.
Professor Farrar, of the Cambridge University, Mass., in describing a storm that passed over Boston on 23d September, 1815, (the account of which was published in the American Philosophical Transactions 1819) says, that he could not determine the place of the center or the limits of this storm, but noticed the veering of the wind, and the fact, that it veered in opposite directions at Boston and New York at the same time.
Before this, in 1801, Colonel James Capper published a work entitled "Observations on the winds and monsoons," in which he speaks of great whirlwinds on the Coromandel coast, the centers of which pass generally, near Madras or Pulicat, and whose diameter, he says, cannot exceed one hundred and twenty miles.
The above would seem to indicate that both Romme and Capper had noticed the rotary motion of the wind in storms; but it also appears that they considered these storms merely local, and they had evidently not conceived the idea that the great ocean storms might be governed by the same laws.
In the year 1831, Mr. Wm. Redfield, an American philosopher, published in the American Journal of Science, a paper, in which he demonstrated not only that the storms on the American coast were whirlwinds, but also that they had a progressive or forward movement, travelling on curved tracks at a considerable rate, and were traceable from the West Indies, along the coast of the United States, curving off to the eastward at some point between the Bermudas and the banks of Newfoundland.
While Mr. Redfield was employed collecting the data from which he eventually deduced his law of storms, a similar investigation was going on in Germany. A number of gales had attracted the attention of German meteorologists, chiefly on account of the oscillations and great fall of the barometer, before and during these gales. On Christmas eve, 1821, the barometer sank so low that many people believed their barometers were out of order, and others, who were not mistaken as to the cause, expected a great catastrophe.
Professor Brandes, a German meteorologist, who had kept a record of observations for a length of time, obtained the registers kept at various places during the same time, and eventually advanced a theory, that the winds, during these great storms, blew from all points of the compass in straight lines toward a central space where the barometer was for the time at its lowest stand.
The theory of Mr. Brandes was disputed by professor Dove of Berlin, who subjected the observations to a new examination, and made it appear that an explanation of all the phenomena was afforded by the assumption of one or more circular currents or whirlwinds of great diameters, advancing from S.W. to N.E. A full account of this is found on page 162, Dove's Law of Storms, 2nd. Edition 1862.
Professor Dove's theory, although under discussion about the same time that Mr. Redfield by an independent course of investigation arrived at the results above mentioned, was not known in the United States when the latter gentleman published his paper in the American Journal of Science, and an eminent English philosopher, named Sir David Brewster, is accredited with saying in connection with Redfield's discovery: "The theory of rotary storms was first suggested by Colonel Capper, but we must claim for Mr. Redfield the greater honor of have fully investigated the subject, and apparently established the theory upon an impregnable basis. Mr. Redfield had no knowledge of Col. Capper's discovery, when he published his own in 1831."
In the year 1838, Lieutenant Colonel Reid, of the royal engineers, published a valuable work entitled "Reid on the law of Storms," in which he agreed in all particulars with the views of Redfield, and verified by personal observation all his theory; adding many substantial proofs to the same by investigations of some of the West India hurricanes, and of some in the southern Indian Ocean.
Colonel Reid by his observations of storms in this latter sea further proves Mr. Redfield's theory, that, the storms in the southern hemisphere revolve in a contrary direction, to those in the northern hemisphere. Colonel Reid embodied in his work many useful rules for maneuvering in a revolving storm, and thus may be said to have reduced the science from a mere speculative theory to a practical law; and the recorded experience of hundreds of able and observing men who have carefully and intelligently noted and studied the course and gradual veering of the wind within the limits of the storm disk goes to prove, that correct conclusions have been arrived at in this respect, and that in every part of the world where these storms have been met with, the winds rotate in concentric circles, with greater or less velocity according to the distance from the center; from right to left in the northern hemisphere, and from left to right in the southern hemisphere; but these principles are so well known that it is unnecessary here to dwell upon them.
With respect, however, to the cause or origin of cyclones we are still comparatively in the dark, and as it is not my purpose to introduce any new theory, nor even to criticize existing ones, except so far as they may conflict with my own views, I shall confine myself to a brief recital of the opinions of a few gentlemen who appear to have given the subject careful consideration, and spent much time and labor in the prosecution of their investigations; and whom, I would add, though time shall prove all their theories wrong, are nevertheless entitled to the gratitude of all the world, and particularly to the love and reverence of "those who go down to the sea in ships."
Mr. Redfield appears to have had no particular theory as to the causes of cyclones; he thought it would be unscientific to attempt to account for them, until better informed, by the exclusive action of any one or more causes. Later, however, he inclines to think them produced by the conflicts of prevailing currents in the different strata of the atmosphere giving rise to circular movements, which increase and dilate to storms.
Colonel Reid avoids any general speculation as to the causes of cyclones. He adverts to the possibility of there being some connection between storms and electricity and magnetism, and concludes with an account of an experiment with a ten inch hollow shot, which he thinks, partly confirms his views.
Professor Dove accounts for cyclones, by currents of air near the equator being from any cause set in motion toward the poles and coming in contact with other currents moving in a different direction.
Mr. Piddington, the author of the Sailor's Horn-book, in the 3d edition of that work, (1860) pp. 324, 325 and following pages, gives it as his opinion that cyclones are purely electrical phenomena formed in the higher regions of the atmosphere, and descending in a flattened disk-like shape to the surface of the ocean, where they progress more or less rapidly, according to circumstances. He thinks that whirlwinds, dust-storms and water spouts are the same meteor in a concentrated form, but cannot say where the law which regulates the motions of the larger kinds ceases to be an invariable one.
The views of Sir John Herschel on the causes of cyclones, says Mr. Piddington, (Sailor's Hornbook, page 21) may be briefly stated as follows:
"It seems worth inquiry whether hurricanes in tropical climates may not arise from portions of the upper currents prematurely diverted downwards before their relative velocity has been sufficiently reduced by friction on, and gradually mixing with, the lower strata; and so dashing upon the earth with that tremendous velocity, which gives them their destructive character, and of which hardly any rational account has yet been given. Their course, generally speaking, is in opposition to the regular trade winds, as it ought to be in conformity with this idea." He then goes on to say that it does not follow that this must always be the case, for, "in general, a rapid transfer, either way in latitude, of any mass of air which local or temporary causes might carry above the immediate reach of the friction of the earth's surface, would give a fearful exaggeration to its velocity. Wherever such a mass should strike the earth a hurricane might arise, and should two such masses encounter in mid-air, a tornado of any degree of intensity on record might easily result from their combination."
Sir John Herschel also alludes to the possibility of the meeting of two atmospheric undulations or barometric waves travelling in different directions, producing a storm and giving a rotary motion to the wind.
Professor Espy, an American philosopher, in his fourth meteorological report, 1857, page 11, gives as one of the causes of storms the following : upon any partial heating of the air at the surface of the earth it rises in columns more or less charged with vapor, which as they rise have their vapor condensed into clouds or rain. Next in this changing of state the vapor communicates its latent caloric to the surrounding air, which also expands, is cooled itself by that expansion, but also gives heat to that part of the air in which it is then, and becoming lighter is carried farther up. In short Mr. Espy considers the center of a storm the base of a huge moving chimney circular or of any longitudinal shape, the draught of which is occasioned by an extensive condensation of vapor above.
Dr. Alexander Thorn, in a work on storms in the Indian ocean, south of the equator, gives it as his opinion that circular motion is given to the winds in a storm area by the contact in meeting on the borders of the monsoons and trade winds of opposing currents of air, differing in temperature, humidity, specific gravity and electricity. These he thinks give rise to a revolving action which originates the storm.
It is believed by some that cyclones originate at great volcanic centers, and Mr. Henry Piddington is among that number. On page twenty-three, sailor's Hornbook, I find the following : "If we produce at both ends the line of the track of the Cuba cyclone of 184-4, we shall find that it extends from the great and highly active volcano of Cosseguina on the Pacific shore of Central America, to Hecla in Iceland. And in 1821, the breaking out of the great volcano of Eyafjeld Yokul in Iceland which had been quiet since 1612, was followed all over Europe by dreadful storms of wind, hail and rain."
A late writer, (Professor Silas Bent) in an article published in the St. Louis Republican, Nov. 3d 1878, gives the following interesting solution of the cyclone problem, viz : "By the earth's rotation on its axis, objects on its surface between the tropics are carried from west to east at the rate of a thousand miles per hour, whilst, as we advance towards the poles, this rate decreases with the decrease in the circumference of the parallels of latitude, so that when we arrive at points where the circumference is only twelve thousand miles instead of twenty-four thousand as it is at the equator, this velocity of rotation is but five hundred miles an hour, and so on, decreasing until reaching the pole."
"Now an object set in motion towards the equator, from the polar regions, where the velocity of the rotation is small, will constantly be arriving at points on the earth's surface where the velocity is greater, and, not at once acquiring this greater velocity, its direction will tend obliquely to the westward. Hence we find those streams or currents which flow from the pole towards the equator, always taking a southwestwardly direction, whenever the continents and islands will permit. As another and perhaps more forcible illustration let us suppose that a cannon at the pole be fired in the direction of Mount Chimborazo, on the equator, and that the ball travels at the rate of one thousand miles per hour. The distance from the pole to the equator being in round numbers six thousand miles, it would take the ball six hours to reach the equator; but, during that interval, Chimborazo has been whirled six thousand miles to the eastward and the ball would strike the equator six thousand miles to the westward of the mountain, and in its flight would have made a due southwest course from its point of starting. The result would be the same, of course, whether the ball be fired from the south or the north pole, and this shows why the trade winds, which strive to take the shortest flight towards the equator, are swept to the westward and are given their oblique direction."
"For similar reasons all ocean and atmospheric currents, flowing from the equator towards the poles, being subject to the same physical laws, are thrown to the eastward in both hemispheres."
"Fluids flowing freely towards a center always assume a rotary movement, as is seen in wash basins when the plug is removed from the waste hole."
"Now let us suppose that a disturbance in the equilibrium of the atmosphere has taken place by which a lessened atmospheric pressure or partial vacuum occurs a number of degrees north of the equator, and to restore which the surrounding air is set in motion towards this common center."
"The air nearest the equator, in moving north, will be thrown to the eastward; whilst that to the north of the vacuum, in flowing south, will be thrown to the westward; but both will at the same time be pressed inwardly towards the vortex by the heavy mass of the atmosphere without, and these two movements in opposite directions and on opposite sides of the incipient storm will give a revolving direction from left to right (right to left?) to all intervening portions of the atmosphere to complete the gigantic whirlwind which is thus generated."
"Shift the phenomenon to the southern hemisphere, and all the characteristics remain the same, but the rotation of the storm will, under the operation of precisely the same physical causes, be in the reverse direction; that is, it will be from right to left (left to right?) or with the hand of a watch, instead of from left to right (right to left?) as described in the northern hemisphere."
Before closing this part of the subject I must refer to another writer of some prominence in meteorology, Professor Wm. Blasius, whose book entitled "Storms, their nature, classification and Laws" was published in 1875 and shows its author to be a profound thinker and indefatigable investigator in search of truth. The space in this paper does not admit of a rehearsal of his theory, but a full and exhaustive account of it will be found in his book on storms above mentioned, page 44 and following pages, and also Appendix A of the same book, page 256 and following pages.
His laws governing the motion of the wind in a storm are most singular and entirely at variance with anything heretofore heard of or experienced by seamen; and his rules for avoiding the dangerous portion of a storm are very extraordinary. Thus on page two hundred forty-three he says: "In the temperate zone, if the cumulo-stratus, indicating a southeast storm is seen above the southern horizon, there is no danger, because the storm will go south. If it appears in the north, it will approach with the dangerous region in advance, and it is wisest to sail by the shortest course to the outside of the track, guided by the position of the cloud and its progressive direction. If the storm is yet distant this may be easy. If however a vessel should find herself immediately in front of the middle of a southeast storm, not yet fully developed, the wisest course is probably to sail straight through the region of calm into the polar current."
I presume the professor in his last remark has reference to a steamer.
With respect to the centripetal or inblowing theory, advocated and developed by Professor Espy of Philadelphia, Mr. Blasius says (page 39) that it contains more of the germs of truth than the cyclone theory, and he admits that it is true as far as it goes, but that it is in the position of a part of the truth seeking to take the place of the whole truth. Now if the centripetal theory is true as far as it goes, then every ship scudding in a storm must run into the center, and that we know is not true; for there is no case on record nor is it known in the experience of any seaman that a vessel has ever got into the center of a cyclone by scudding, except, when she has attempted to cross the storm track when the distance of the center and the velocity of the storm on its track rendered such a thing impossible. I ought to say that there is no well authenticated case on record, for there is indeed a case recorded in the book on Storms by Professor Blasius above referred to, which may be found on page 241 of that work, as follows: "Mr. Meldrum has published a treatise to prove that cyclones are not circular but elliptical in shape, formed between two opposing currents of air, and states that the rules based on its being circular frequently carry vessels into the dangerous section instead of around it. He cites the startling fact that on February 25, 1860, forty-one vessels left the roadstead of Reunion island with a south-easterly wind, which, according to the old law of storms, placed the vortex to the northeast, and these vessels sailed to the northwest to avoid it. The result demonstrated that the central vortex was really to the N.N.W., so that they ran directly into it, and only four of them, one a steamer, succeeded in crossing the storm path. As for the remaining thirty-seven, only seven escaped total loss or very great injury.
In the proper place in this paper I will again refer to this case; and it is perhaps proper to state here also, that in a foot-note on page 241, Professor Blasius says that he was obliged to rely for the above quotation on a newspaper paragraph, having been unable to obtain Mr. Meldrum's treatise.
Other opinions on the origin of cyclones are not wanting; but the object of this paper being not to deal so much with the theoretical cause of cyclones as with the effect and the practical application of the theory, I will close this part of the subject here, and pass to the narration of a few facts gathered by myself from original sources.
Professor Blasius in his book on storms page 240 says: " In the first place it is deduced from our principles that the rotary or cyclone theory is radically wrong, and the rules for navigators which are based on it worse than useless." Let us examine and see how far this statement is borne out by facts.
On the twenty-fifth of August, 1872, while attached to the U.S.S. Idaho at anchor in the harbor of Yokohama, Japan, a cyclone passed over that place; and I was enabled, from my fixed and secure position onboard the ship, to observe accurately all the phenomena of the storm, which I did and of which I here give an abstract.
At four P. M. the storm commenced, wind at E.S.E. force 6 to 9, barometer 29. 28 in. thermometer 80° and the weather overcast and squally with rain.
At five P. M. wind still E.S.E., force from 9 to 10, barometer 29.14 in. having fallen 0.14, during the hour, heavy clouds resting on the water, and the squalls coming with redoubled force at shorter intervals than during the preceding hour.
At six P. M. wind E.S.E. ¼ E., force from 9 to 11, barometer 28.94 in., having fallen 0.20, during the hour ; clouds darker and if possible thicker, and the rain pouring down in torrents.
At seven P. M. wind E.S.E. ½ E., force 11 to 12, barometer 28.50 in., having fallen 0.44 during the hour. Up to this time the wind had blown in squalls, lasting from three to five minutes, which are represented by the highest figures here given to denote force of the wind while the lower figures indicate the force of the steady gale; but during the five minutes succeeding seven P. M. the wind blew with a steady force which I cannot describe by any language at my command except, perhaps, by comparison. In which case I would say, that this terrific blast bore the same relation to the highest steady force of the storm previously experienced that an ordinary fresh gale bears to a light breeze; and the rain, which continued to fall in torrents, was blown by the force of the wind into such fine particles that it assumed the appearance of a moist vapor driven furiously before the storm, but notwithstanding it fell so fast on the Idaho's deck that the scuppers were insufficient to carry it off. During this blast, an English bark at anchor in the harbor near the Idaho, which had not at all moved during the rest of the storm, picked up her moorings and dragged past the Idaho at the rate of, I judged, about six knots, and had the blast lasted ten minutes longer she must have brought up on the Kanagawa shore, but at 7.05 P. M. the blast was over, and the wind gradually subsided, veering as it did so to the southward, and shortly after an entire calm followed.
The barometer still kept falling, and at 7.15 P. M. it stood at 28.35 in., having fallen 0.15 in. in fifteen minutes. During the calm the weather was fine, the rain had entirely ceased, and the sky overhead was partially clear. At 7.30 P. M., the barometer reached its lowest stand, 28.27 in., having fallen 0.08 in. in fifteen minutes. The calm lasted about half an hour. At 7.45 light airs were felt from N.W. and at 8.00 the shift came in force from W.N.W. ½ W. with a re-appearance of rain and violent squalls. The barometer, in the mean time, had commenced to rise, standing at 8.00 P. M. at 28.32 in. At 9.00 the wind was W. by N. and barometer 28.70 in., showing a rise of 0.38 in. during the hour; the wind at this time blew with a force of from 8 to 10. At 10.00 P. M. the wind had veered to west and moderated to a strong breeze; barometer stood at 28.93, showing a rise of 0.23 in. during the hour. The rain at this time ceased. At 11 P. M. wind had moderated to a light breeze, and soon after died away altogether, blue sky appeared and barometer rose to 28.99 in.
The storm had passed, travelling in a direction about N.N.E. at the rate of fifteen miles an hour, and its diameter was about one hundred and five miles. I had excellent opportunity for obtaining data relating to this storm and the above figures are very close approximations to the truth. A remarkable feature of this storm was the almost total absence of lightning, for, with the exception of a few very vivid flashes on either side of the center, there was no appearance of any electrical phenomena during the entire passage of the storm over the ship. I observed also during the passage of this storm over the Idaho, at irregular intervals, sometimes during, and at other times between the squalls, a violent vibration of the magnetic needle, which was not caused by the movement of the ship nor by any vibration communicated to the compass by the force of the wind causing the ship to tremble as she did during the heavy squalls and the final blast; and I can only account for this by the assumption of a strong magnetic force being distributed in veins or bauds through portions of the atmosphere in the storm disk.
The above facts speak for themselves, and, having observed them myself, I am certain of their correctness. The one thing I cannot do is to reconcile them with the centripetal or any other than the cyclonic or circular theory.
FORMOSA CYCLONE.
The British ship Argyleshire, on a passage from Hong Kong to Yokohama, encountered, on the 11th September 1872, at midnight, a cyclone near the south end of Formosa; Botel Tobago island bearing N.E. twenty-three miles, when the wind commenced to blow fresh from N.N.E., accompanied by all the usual signs of bad weather, and the captain rightly concluded that he was on the border of a cyclone; but somewhat hastily, and, as I will show, wrongly, decided that he was in left semicircle.
On the diagram marked Formosa, Plate I. Fig. I, I have plotted the track of the ship from the time of her entrance into, to the time of her departure from the storm disk, the courses and distances, being the true courses and distances, resulting from a careful computation of the data found in her log. Points of reference on the track are marked 1, 2, 3, &c.
Fig. 2. shows the actual position of the ship in the storm disk, plotted by bearing and distance from the center, and the points of reference 1, 2, 3 &c correspond to the same numbers on the track.
I have also drawn roughly the coast line of Formosa, in order to show the relative positions of ship and laud, and also to illustrate the effect of high land upon the wind in a cyclone.
By an examination of the log book of the British bark Malvera, I found that she had passed through a portion of the same storm, and, by the data contained in her log, I was enabled to locate the center fifty-five hours after it had passed the Argyleshire, during which time it had travelled W. by S. four hundred and sixty-one miles. This of course is only approximate, but it is probably not far from the truth, and I have therefore constructed this diagram on the assumption of a uniform rate of speed of 8.4 miles per hour W. by S. With this, and the data found in the Argyleshire's log, I have also computed its diameter to be about five hundred eighty eight miles.
But to return to the ship we find her on the border of the cyclone (Pt. I) having the wind from N.N.E. and the center bearing according to the accepted theory of the law of storms : E.S.E., barometer 29.95 in., weather overcast and cloudy. The captain, believing that the storm was moving northward, decided that he was in the left semicircle, and accordingly continued on his way making good a course E. by S. (on the port tack) for a distance of sixty-three and a half miles, during an interval of five hours and eighteen minutes. At this point (Pt. 2), the wind had increased so as to oblige him to shorten sail, and the barometer had fallen to 29.70 in., the squalls become stronger, more frequent and of longer duration. He still continued on his course believing that the center would pass northward far enough ere he could reach the line of its axis to enable him to take advantage of the westerly and south westerly winds, which he expected to meet with in the south and south-eastern parts of the storm circle; but at the expiration of three hours the wind had increased to a moderate gale, blowing from N.N.E. ¼ E., barometer had fallen to 29.32 in. and the condition of the weather grown very much worse. During the last three hours he had made good a course E.S.E. 5/8 E. thirty miles (Pt. 3). Sail was again reduced and during two and a half hours more he ran S.E. ¾ S., twenty-six miles (Pt. 4.) At this point the wind had increased to afresh gale, blowing from N.N.E. ¾ E., barometer had fallen to 29.12 in. and the weather assumed a very threatening appearance, overcast, with heavy squalls, rain and lightning. Still believing himself in the left semicircle, (notwithstanding everything indicated the contrary), but finding that he was nearing the center, he concluded to bring the ship by the wind, and await the opportune moment for resuming his course. The ship was accordingly put under close reefs and storm canvas, on the port tack head-reaching, and was so kept about one and a half hours, when at noon, on the 12th, (Pt. 5), the wind had increased to a strong gale (10) barometer, fallen to 29.02 in., wind changed to N.E, ½ N. and the weather steadily growing worse, the captain evidently began to think that he was approaching the center rapidly, and his hopes of fair westerly and south-westerly winds, died away with the first gleam of an idea that he might have been mistaken as to the course of the storm. Be that as it may, he wore ship and hove her to on the starboard tack. He drifted in this way during three and a half hours to (Pt. 6) where the wind, blowing furiously, had changed to East, but the barometer, during the interval, had remained steady. During five hours more the wind continued blowing with unabated force, gradually veering to the southward, and at the end of this interval was S.E. by E. ¾ E. and the barometer had gone up to 29.23 in. (Pt. 7). During the following thirteen and a half hours of this storm, the barometer rose gradually to 29.58 in. and the wind, veering slowly, was at about 10.00 A. M., September 13th, S.E. ½ E. blowing a fresh gale, and rapidly moderating. At this time the lightning had entirely ceased and the general appearance of the weather very much improved (Pt. 9.) Sail was now made on the ship and during the remaining eight and one half hours within the storm disk she made good a course S.E. ¾ E. fifty-six miles, and about 6.30 P. M. on the 13th September she passed out of the storm-circle (Pt. 11) the wind being S.E., blowing a fresh breeze, and the barometer at 29.90 in. The thermometer ranged from 71° to 79° being 78° at the point of entrance into the storm disk, 79° at the point nearest the center and 71° at the point of leaving the storm circle.
LINCHOTEN CYCLONE.
On the diagram marked Linchoten, Plate II, Fig. 1, I have plotted the track of the Francis Henty (bark) of Melbourne, as it appears from a careful computation of the data in her log-book, and a second track
which results from the application of a current to all the courses. Fig. 2. shows the position of the ship in the storm circle, plotted by bearing and distance from the center.
The rate of the storm's progressive movement was ascertained to be about sixteen miles an hour. By working up the data found in the logbook of the British bark Hilda which passed through the same storm, I was enabled to locate the center thirty-five hours after it passed the Francis Henty, haying traveled during the interval about five hundred and sixty miles north-eastwardly.
With these figures and the Francis Henty's log, I have computed the diameter of the storm to be about three hundred and sixty miles; and the diagram is accordingly constructed on the basis of the above figures.
The Colonial bark Francis Henty of Melbourne, commanded by Mr. W. T. Ouayle, left the Saddles, off the mouth of the Yangtze river, China, on the 4th October, 1872, bound for Yokohama, but owing to contrary wind she was unable to fetch the Strait of Van Diemen, and so was obliged to bear up for Colnett strait. Before reaching this point, however, the captain discovered indications of a cyclone to the southward, and decided to remain on the western side of the islands, and await the result of the coming gale. His barometer was low and indicated great agitation in the atmosphere by a constant oscillation of the mercury in the tube, and this considered, together with a heavy cross-swell, occasional flashes of lightning, and a general threatening appearance of the weather, left little doubt that a storm was not far distant. On the morning of the 8th October, being then in the vicinity of Yoko sima island, the barometer rose 0.20 in. from 29.30 in. to 29.50 in. and this circumstance threw the captain off his guard; he thought the danger was all over, and, believing the storm was passing away from him, he took advantage of a slant, to pass through close hauled on the port tack between the islands of Tokare sima and Yoko sima; but the wind hauling to the eastward headed him off, and when be had reached a point about eight and a half miles N.E. ¾ E. from cape Monturose, it was E.S.E. still hauling to the southward and rapidly increasing in force, blowing at the time a strong breeze. The vessel was here put on the starboard tack, and kept free with a view to repass to the westward of the islands, as it was now evident that the storm was approaching, notwithstanding the rise in the barometer. While running to the northward the barometer still kept rising, and actually rose 0.20 in, more, viz. from 29.50 in. to 29.70 in., but the wind at the same time continued to increase in force, and the clouds came rushing on so fast and thick, that the question of passing through the chain of islands to the westward became a very doubtful maneuver, attended, if attempted, with incalculable risk, considering the force of the gale blowing, and the impossibility of seeing far enough ahead to avoid an island or a rock, should one happen to be in the way. The vessel was therefore hauled up on a course nearly parallel to the trend of the islands, and sail reduced. The barometer soon ceased to puzzle the captain; it commenced to fall much more rapidly than it had risen, and that and the wind told the whole truth. The storm was coming direct for the ship, the latter having no possible way of escape.
The facts, as they occurred during this storm, are as follows :—At 7 P. M., October 8th, we find the Francis Henty at a point N.E. ¾ E. eight and one-half miles from cape Monturose, the N.E. point of the island of Oho sima (Pt. 1.). From this point she steered to the northward and eastward for Colnett strait; running with the wind from S.E. by S. blowing a moderate gale; the weather was overcast, squally and rainy, and the sea rough. During a run of two hours, she made good a course K by E. J E. sixteen miles (Pt. 2). The barometer, during this interval, had fallen 1.05 in. from 29.70 in. to 28.65 in. and the wind had increased to a fresh gale (9). The clouds also had descended to the water surface in a solid wall of deep black, and enveloped the ship in a dense mist: this added to the natural obscurity of the night, rendered the darkness intense, which was relieved only by occasional flashes of lightning. The idea of passing to the westward of the islands was abandoned, and the ship was hauled off on a course nearly parallel to the trend of the islands, under double reefs and reefed courses. She ran in this way during an interval of three and three fourths hours, and made good a course N.N.E. twenty-seven and a half miles; at this point (Pt. 3) the wind was S.E. ¾ S., having increased to a strong gale, (10) and the barometer had fallen 0.35 in. to 28.30 in. The vessel was then put under close reefs, and the mainsail furled; and under two close-reefed topsails, foresail and lower staysails, she was kept a good full, with the yards braced well in, in order to gain ground if possible to the eastward. This heavy press of canvas was kept on until a violent gust split and carried away all her square sails, broke the main yard short off in the slings, and sprung the foreyard. In this condition she was brought to, under storm staysails, on the starboard tack, having made good a course N.E. ¼ N. twelve miles (Pt. 4.) while trying to make easting and, if possible, distance the center, which, there had been no doubt when the maneuver was commenced, was coming direct for the ship, and hence these desperate efforts to avoid it. At this point the wind was S.E. ½ S., blowing a terrific gale (11) barometer 27.50 in. (having fallen 0.80 in. in one and three-fourths hours) and the condition of the weather beyond description. To use the captain's own expression in speaking of the lightning, he said: "It came tumbling down on all sides in vertical columns of vivid green," and in trying to convey to me a general idea of the surroundings at the time, he added in substance the following : "while laying to and trying to clear away the wreck as much as possible, the sea, though running high, did not break, owing to the pressure of the wind upon it. The wind steadily increased and the gusts became stronger, and more frequent, until it was thought impossible for the wind to blow any harder; and yet it increased and increased again till the noise became deafening. The howling of the wind, the roaring of the waves, and the creaking of hull, spars and rigging was something terrific, added to which, the dreadfully vivid glare of the now almost constant sheet of lightning, rendered the momentary intervals of darkness, the darkest of the dark." To a question as to whether or not he heard any thunder, the Captain answered : "I cannot say, but I don't think any thunder could have been heard above that terrible noise."
The ship had drifted about three and one-half hours in a helpless condition, (enveloped in a dense cloud of rain and spray, driven furiously against and over the ship, the men being lashed on deck), when the captain thought of his barometer, and on examination found it standing at 27.19 in. A few minutes later when he again looked at it, the mercury had fallen out of sight, he did not know how far. The wind at this time was S.E. ¾ S., and, almost immediately after examining the barometer the second time, he felt one terrific gust strike the ship, under the pressure of which she listed over until her yard-arms touched the water, and so remained for about a quarter hour, when the wind suddenly lulled, and during an interval of from five to ten minutes, gradually grew weaker, until eventually it died away entirely; and, in the place where but a few moments before, nature had raged in all her wildest furies, reigned at this time (6.30 A. M., Oct. 9th,) an absolute calm. The ship had drifted at an estimated rate of five and one-half knots an hour, and I have therefore allowed, N.W. t N., twenty-two miles of drift for the four hours since she was hove to—(Pt. 5). After the ship had passed into the calm space, and the noise of the wind and sea had somewhat subsided, it was discovered, that the fore and main top-gallant masts and the mizzen top-mast had all been carried away, and shortly after a heavy sea came over forward, which, in its passage, carried the jib-boom with it.
Although the wind had ceased, the danger was by no means lessened, for the sea ran so high, and with such fearful irregularity, that the probability of foundering was very great. While tossing about in this way she shipped seas from all directions, and stove in her bulwarks on both sides between the fore-castle and poop; breaking several of the stanchions just above the covering board, and as if to fill the cup of bitterness to the brim, in these moments of anxiety and dread, the main-hatch was partly blown out by the expansion of the air below, which, having a greater specific gravity than that on the outside, and exerting an outside pressure of more than one pound to the square inch, (the barometer having fallen two and a-half inches since entering the storm disk) naturally sought to establish an equilibrium through the weakest part of the ship.
While trying to secure the hatch to prevent the water from rushing down into the ship's hold, the second mate, who was at that work, was washed overboard by a sea coming over the starboard beam, and was actually tossed back again, by another which came on board over the port-side. I mention this circumstance to show how irregular the sea must have been. The captain described the seas in the calm center, as so many church steeples, rising, tottering, and falling in the wildest confusion.
To a question as to how the clouds or atmosphere appeared in the center he answered: "The central space was filled by a thick, gray haze or fog, through which, at intervals, I saw blue sky. The rain had ceased, but lightning, in a less degree, still continued." But to return to the ship; we find her tossing about in the center of a cyclone, perfectly unmanageable, with her top-gallant-masts, mizzen-top-mast, head booms and main yard gone, fore-yard sprung, and nearly all her sails blown away, with the certainty of having to encounter another part of the storm equally as violent as the one she had just passed through. In order to avoid being driven against a heavy sea on the lee quarter, when the wind, as he expected, should come out from N.W., the captain decided to put the ship on the port tack; but how to accomplish this without any sails or wind was the question. He rightly conjectured, however, that a few light puffs would probably precede the strong blast on the other side of the center, and thought he would have time to point the ship's head in the right direction if he had but some sail forward. He did not dare open his sail-lockers for fear of swamping or filling the ship with water, and he had nothing but a storm staysail left forward with which to attempt to wear, or rather to point the ship's head. A three cornered lower-studding-sail, lashed under the forecastle deck was, however, thought of at this moment, and it was quickly got out and secured to the fore-yard on the starboard yard-arm from the slings out, keeping the sheet on deck, made fast to the bitts near the mast. By these means he managed to point the ship's head to the N.E. during some little gusts of wind on the rear edge of the calm center, and when the wind came out in force she received it on the port side. The wind came out from N. W. with such force that she was again thrown down, nearly on her beam-ends. Having lost, however, her upper spars, she righted a little, after the first tremendous gust had passed, but still, during the next half hour, the wind forced her over so that she was drifting with her lee scuppers under water, against a sea, which, under the impetus it had received from the S.E. wind in the first part of the storm disk, was still running with considerable force from that direction. I will not attempt to describe the horrors of that half hour, during which it was expected every moment that the deck would be crushed in by the sea; and this would probably have occurred if the bulwarks had not previously been carried away; as it was, the sea made a clean breach over the vessel without stop or hindrance. The sea, however, soon yielded to the tremendous force of the wind and continued during the heaviest blow comparatively smooth. She drifted in this way for two and a half hours about fourteen miles S.E. ¾ E., (Pt. 6) the wind blowing a hurricane from N.W. under the same circumstances of weather as already described on the other side of the center, with the single exception of it being day 9.30 A. M. instead of night, as was the case before. About this time the wind moderated a little and the ship righted, the barometer was examined and registered 27.20 in. The sea commenced to rise with the abatement of the wind. During the next one and a half hours the wind blew with an estimated force of (11) and had veered to N.W. by W. ¾ W., barometer went up to 27.25 in. and the ship drifted E.S.E. ¼ E., seven miles (Pt. 7). The story of this storm, at least that part which properly comes within the scope of this paper, is now told; and the only remaining feature to which I will call attention is the veering of the wind to the southward, as the ship approaches the island of Oho sima. Thus at (Pt. 8) wind is W. ¾ N. blowing a strong gale (10) barometer 27.75 in. and ship has made seven miles E. ¾ S. At (Pt. 9) the wind is S.W., blowing a fresh gale (9) barometer 28.00 in. and ship has made six miles E. ¾ N. At (Pt. 10) the wind is S.W. by W., barometer 28.40 in. and ship has made five miles E.N.E. ¾ E. At (Pt. 11) the wind is S.W., blowing a moderate gale (8) barometer 29.10 in. and the ship has made five miles N.E. by E. f E., weather clearing. At (Pt. 12) the wind is S.W., blowing a fresh breeze (7) barometer 29. 40 in. and ship has made five miles N.E. ¾ E. At this time 6.30 P.M., Oct. 9th, she was found to be about seven miles N.N.E. from Sandown rocks, after having passed through the most violent storm that I have ever heard an eye-witness describe, and, after an interval of twenty-three and a half hours of sailing and drifting, she found herself only nineteen miles from the point where she started the previous evening at seven. I will here leave the Francis Henty to make the best of her way to Yokohama.
Before proceeding farther I will briefly explain the two tracks shown on this diagram. The upper track is the one resulting from the plotting of courses and distances sailed, and the measured and estimated drift as per ship's log; but the ship, at the end of the storm, was found seventy-one miles S. 52° W. from the point where the log placed her, and as I have no means of accounting for this difference, I have assumed that a uniform current of three knots per hour, setting S. 52° W., affected the course of the ship during her passage through the storm disk, and the lower track, resulting from the application of this current to all the courses, is approximately the one over which the ship passed. As, however, the major part of this surface set must have been produced by the storm, the ship was probably, not so much affected by it in the beginning as in the latter part, and, her true track lies somewhere between the two here plotted.
It is a significant fact that the Francis Henty was set to the S.W. rapidly by the same current after the storm was over.
It is not unusual to find, what is known as the storm wave setting strongly in the direction of the course of the storm; but it will be observed that this current came from nearly an opposite point, and I am at a loss to account for it, except upon the assumption that the surface waters were driven furiously against the islands by the S.E. winds, and not finding ready means of escape through the passages between them, were turned off to the southward, through the wide and clear passage between the island of Oho sima and the islands to the westward.
Review.—I will now briefly review the two last cases, and examine the evidence before us; my object being to show that the wind within the storm disk of a cyclone, blows, as the word implies, in a sort of spiral curve resembling the coil of a snake, which for all practical purposes may be considered a circle. In other words, that the winds blow in circles round a common center ; subject, however, to certain
modifications growing out of the contact with land; the extremes of which I believe are to be found in the two cases here represented, for which reason I have selected them as the subject of my paper; and I regard them, whether considered separately or together, as typical of the cyclone with all its variations.
In the first case, we have the Formosa cyclone moving W. by S. and coming in contact during its course with the south end of Formosa island. We notice that the long arrows which indicate the direction of the wind as registered on board the Argyleshire come from a point northward of that shown by the short arrows, which represent the wind as it ought to blow according to the cyclone theory, until the ship comes near a perpendicular, from the center, raised on the line of its axis (Pt. 6) after passing which we find the long arrows coming from a direction south of that indicated by the short arrows (Pt. 7) and, again as the ship approaches the edge of the eastern or rear portion of the storm disk, the difference in direction of the arrows grows gradually less, until at (Pt. 10) the coincidence is nearly perfect. Let us notice also in this connection that at (Pt. 9) a perpendicular from the center, falls westward of the south point of Formosa, and that the influence of the land upon the wind grows gradually less as the center passes westward. Now if we consider a cyclone travelling eight and a half miles an hour and coming in contact suddenly with a mass of high lands, such as we see on the south end of Formosa, where a mountain range runs parallel with the coast and rising from nine thousand to eleven thousand feet above the sea, and several peaks south of it ranging in height from two thousand to nine thousand feet, it is but reasonable to suppose, that something must give way, and that something is the wind. The first effect is to check the course of that part of the storm disk actually in contact with the land, and next, the wind in the struggle for liberty naturally turns toward the side where it meets with the least resistance, viz., the center of the storm.
While this is going on in front, the rear part of the storm is partly checked in its turn, but still pressing forward, and the result is a distortion of the storm disk. The currents of air, instead of passing over the arc of a circle, assume the form of au ellipse more or less irregular according to the nature of the obstruction and the speed with which the storm is moving. All these things considered in connection with the Formosa cyclone I believe will satisfy every question in the problem. As will be seen by the wind arrows on the diagram, while the ship was to the westward of the axis or longest diameter of the ellipse, she had the wind from some direction northward of the cyclone point, and that after passing to the eastward of that line the wind actually blew from some point southward of the cyclone point, which is in perfect accord with the above expressed idea of the distortion of the storm disk. We also notice that after the center has passed the south point of Formosa, and in proportion as it passes farther to the westward of that point, the winds gradually resume their normal direction, (the circular course) and at (Pt. 10) the coincidence of the two arrows is nearly perfect; a fact which would seem to indicate that, had there been no obstruction the wind would have blown in circles throughout the entire area of the storm.
This storm presents another feature of interest not often met with, and if we suppose a ship caught in this storm anywhere within fifty or sixty miles of the south point of the island, on the east coast of Formosa and within the limits of the converging currents, we have the case before us. A vessel so situated would have the wind from N.N.E. and locate the center at the E.S.E. which would at first be true; but this bearing according to the wind would remain the same, during the passage of at least one half the storm disk over the ship, and the barometer falling also, because the center is gradually coming nearer, would indicate, that the storm was actually coming straight towards her.
This is one of the cases where the judgment of the commander may save his ship, and where a want of judgment and nerve will certainly lead to destruction. He has, it is true, no means of determining the course of the storm, but, he knows that its center is to the eastward of the island, and by examination of his chart he will see at once, that whether the course of the storm is westwardly or northwardly, the wind along the coast of that high land would equally be from N.N.E. or parallel to the coast. In his position he is on a lee shore if the storm is travelling westward, and he must run for the south point of the island until clear of it to the southward. If to the contrary the storm is coming straight for him, as the wind and the barometer indicate, his only safety then lies in scudding. Even if the course of the storm is such as to strike some point on the coast south of him he must still run, with the hope of crossing its track ere the dangerous vicinity of the center has advanced far enough to do him any serious harm; and if the course of the storm forms anything less than a right angle with the coast line he may reasonably expect to accomplish this; for there is scarcely any danger of the entire storm leaping over mountains eleven thousand feet high, if it has room to turn off to the eastward, which it would probably do as soon as the currents in front had banked up against the coast sufficiently to produce a pressure in that direction. In either case his chances for escaping the center are good, and once south of the island, there is plenty of sea room to run out of the storm or heave to and drift as might appear best. If however the course of the storm is westward as in the present case, the question becomes more serious; but it is a question between life and death, the center of a cyclone and a lee shore; and must be decided quickly. To remain hove to in such a position is certain destruction; for, after the center has passed westward of the island, the wind will gradually curve less and less until eventually it strikes the broadside of the coast at a right angle and leaps over the land. By squaring away in time, he may reach the south point of Formosa, ere the center reaches there, but at any rate he must take his chances, and prepare to meet the worst part of the storm in preference to the rocky shores of the island. The chances, however, are all in his favor by scudding, and all against him by heaving to; in the latter case he will certainly bring up on the rocks, in the former he may run into the center; but we know that ships have passed through the center, as did the Francis Henty through one of the most violent storms on record, and come out comparatively all right. The chances are also, and in his favor, that the center of the storm will not pass near enough to the south point of Formosa to bring him into dangerous proximity with it, as the high land would in all probability turn it off to the southward. Once south of the island and hove to on the starboard tack the ship would be in a comparatively safe position. This course of action, however, applies only to high land and a bold coast. If, on the contrary, the land was low and the water shallow for some distance off shore, as on some parts of our own coast, it is a question whether or not, if the storm was moving westward, the safety of the ship would be insured by scudding, or even if such a course would be justifiable; and I am of opinion that it would not. In that case a ship hove to on the starboard tack would be safe until it was found, by her shoaling the water, that she was drifting into dangerous proximity with the land, in which case the last resort would be to drop the heaviest anchor and pay out one hundred and fifty fathoms of cable or more if necessary on the same anchor, and then reduce the surface aloft by sending down spars &c., having a second and third anchor ready, in case of accident to the first or second.
With respect to the Linschoten cyclone, the problem of maneuver is more simple. The captain in this case did all that could be done under the circumstances to avoid the center, with the single exception of passing through the chain of islands to the eastward, when a proper interpretation of the action of the barometer and careful study of the condition of the weather, would decidedly have led the discreet navigator to the adoption of a contrary course; for it is now a pretty well established fact, that, not infrequently, the atmosphere on the border of a cyclone is banked up in front by a temporary resistance to the forward movement of the storm, and thus produces a greater pressure on the barometer, as is seen in the case before us. The barometer here fell one inch in less than two hours after entering the storm disk, and at no time during the ship's presence within its limits did so great a fall occur in the same length of time. The greatest fall registered afterwards was 0.8 inch in one and three quarters hours, from 28.30 inches to 27.50 inches. During the next four hours the barometer fell 0.31 inch from 27.50 to 27.19 inches, but it will be remembered that this was the lowest reading, obtained about half an hour before entering the calm center, and that a few minutes after, when the captain again examined the barometer, the mercury had fallen out of sight, we do not know how far; and I have therefore taken the lowest reading as the minimum pressure. It is, however, quite possible that the barometer in this case fell below 27.00 inches because in the Yokohama cyclone, when near the center the barometer fell 0.15 inch in fifteen minutes and supposing the Francis Henty’s barometer to have fallen at the same rate (and the sudden disappearance of the mercury would seem to indicate that it did) during the half hour following the last reading, it would have fallen 0.30 inch and instead of 29.19 inches would have read 26.89 inches. Assuming this to be true, the Francis Henty exhibits the greatest barometer-fall on record, although not the lowest recorded pressure at the water surface. The greatest recorded fall of the barometer, occurs in the case of the brig Gazelle in the China sea, 1849=2.80 inches from 29.80 inches to 27.00 inches, and the minimum pressure recorded on ship board is given in Piddington's Hornbook, page 264, as 26.30 inches on board the East-India-man Duke of York off Kedgeree, river Ganges 1833. But to return to the case in point, the Francis Henty, we follow her through the first half of the storm and find that the wind blows during the whole interval, from a direction between S. E. by S. and S.E. ¼ S. which, is in strict accordance with the cyclone theory where there is no land to divert its course; and after passing through the center, we also find that the first violent blast is from the N.W., which likewise, is a confirmation of the idea of circular motion knowing that the storm moves N.E. We further notice, that in proportion as the vessel approaches the island of Oho sima, the wind gradually takes a more northerly course in other words, veers to the southward, drawing up the channel between Oho sima and the islands to the westward. This is simply another case of the incurving of the wind already explained in the case of the Formosa cyclone. The only difference between the two being, that in the present case it occurs in the rear portion of the storm disk, while in the other it took place in the fore part of the same.
I have mentioned before, that I selected these two cyclones (the Formosa and the Linschoten) as the subject of my paper, because of the embodiment in them, of nearly the extreme variations of the wind from the cyclone point, and because if dissected and considered in part only there will be found in each of these storms, a sector that would appear to contain the elements of a law upon which another theory (which, by the way, has a great many advocates) is based. I refer to the centripetal or inblowing theory of which Professor Espy of Philadelphia may be considered the author, and which embodies substantially the conclusions arrived at by Professor Brandes of Germany as heretofore mentioned; and I doubt not that an advocate of Mr. Espy's theory, had he been on the spot, would have found ample data in the facts as they occurred to prove it.
Before proceeding farther I would state my opinion, that great ocean storms known as cyclones, &c., are separate and distinct phenomena, created, existing and dying in accordance with certain natural laws, for which no absolute solution has as yet been found; and further, that they have no relation to or connection with the ordinary gales, which do not possess the same characteristics and ought not therefore to be classed in the same category. They are met with in particular localities, and generally at particular seasons, I do not mean to say that a cyclone may not be met with anywhere or at any season, but as a rule, they prevail during particular periods of the year, and are more frequently met with in some seas than in others. The China seas Indian ocean and North Atlantic, appear to be much more frequented by these storms than the South Atlantic or Pacific. They are sometimes met with in the Mediterranean, but rarely, if ever, in the North sea or Baltic, while at the same time gales of wind are common and often very violent in both of the last named seas.
Now it appears to me that some of the modern writers, who condemn the cyclone theory make no distinction between the great ocean storms and ordinary gales, and besides, base their opinions on observation, chiefly made on shore and on theories deduced there from; and while these theories are doubtless the result of much scientific research, of great personal activity and labor and of faithful and honest investigation in search of truth, and also, while the course of reasoning pursued manifests a high order of talent on the part of the writers; yet if these theories do not accord with what actually takes place in a storm at sea, they are worse than useless, they are dangerous to the navigator.
The better to demonstrate this I will briefly compare the centripetal or inblowing theory of Brandes and Espy with the cyclone theory of Redfield and Reid, and take as an example the Francis Henty here represented in the storm disk, her track through which we know and have therefore nothing to suppose. We find her lying in the N.E. quadrant of the storm with the center bearing S.W. by W. (Plate II, Fig. 3. a) and having the wind S.E. by S. Now, according to the centripetal theory with the wind S.E. by S. the center bears N.W. by N.; in other words the ship's position in the storm circle is always on the compass point from which the wind blows and the center always dead to leeward, (Fig. 3. a'). Being on the outside or near the edge of the storm disk and having noticed as did the captain of the Francis Henty the storm approach from the southward, the commander assumes that it is moving northward or north-eastward, and with the center bearing as he believes N.W. by N., he sees a good opportunity to run along with it, and so shapes his course N. by E. ¼ E., but after running for a while he finds his barometer falling and concludes that his course brings him towards the line of the storm track and to avoid this he hauls off to the eastward, first, N.N.E., and then N.E. ¼ N., but ere long, the storm having travelled sixteen miles an hour, while the ship has made only seven or eight knots, the wind has increased to such an extent that all his sails blow away, and he is left in the condition of the Francis Henty, and in the same place, from which there is no escape, and so he meets her fate. (Fig. 3. a center.) This is what he would do in mid-ocean with plenty of room to maneuver on the principle of the centripetal theory. But suppose we reverse the case, and that instead of assuming that the storm is travelling northward, he heaves his ship to, to ascertain its movement, and still finds the wind S.E. by S., he places the center bearing N.W. by N. as before. After having laid to for a time sufficient in his judgment to bring about a change of wind, and having experienced none, he looks at his barometer and discovers a great fall in the mercury, he naturally concludes that the storm is moving directly towards him and so decides to get out of its way. Having the center as he supposes bearing N.W. by N. and the storm moving S.E. by S. he finds that the course which will take him most directly away from the center is S.W. by W., and accordingly he fills away on the port tack (Fig. 3. 6 & h') and runs along with the wind abeam, until his sails blow away as before and he is left in the same place at the mercy of the storm. But if instead of the port tack he fills away on the starboard tack, (Fig. 3. c & c'), as he can do either with the wind S.E. by S.) and stands N.E. by E. it is only a question of a few hours more before the storm will overtake him.
By the above, and by thousands of other cases that might be cited, it is seen that the centripetal theory of the motion of the wind in storms, is not borne out by facts as they occur at sea, and also, that the means which according to that principle should be adopted to escape the center, simply lead a vessel into it; for the reason, that by the assumption that the winds blow in straight lines towards the center, that point is located 90° to the right of its true position in the northern hemisphere, and 90° to the left of its true position, in the southern hemisphere; and yet Professor Blasius says that this theory has more of the germs of truth in it, than the cyclone theory. But the shortest refutation of the centripetal, or any other theory supposing the winds blowing in straight lines towards a point or a line of minimum atmospheric pressures is, the fact, that no ship has ever run into the center of a storm or cyclone by running before the wind, except perhaps, in the vicinity of land when the storm disk was distorted by contact with it, or when near high land under the influence of converging currents of air it was done purposely to avoid a greater evil, and finally, by trying to cross the storm track under circumstances when such an attempt was manifestly improper and the thing impossible.
The Centripetal and Cyclone theories, however, have some things in common; for instance, the changes of the wind occur in the same manner on both sides of the axis or line of forward movement; and according to both theories a vessel may run before the wind along with the storm in the direction of its course; in the former case in its rear on the line of its axis, and in the latter case abreast of the center on a tangent parallel to its course.
These very similarities constitute a real danger to the seaman, who, having read and perhaps studied the writings of anti-cyclonists, that is of the writers above referred to who condemn the cyclone theory, has begun to doubt the truth of the latter, and finding some things in accord in both, (the cyclone and the centripetal theories) is apt to conclude that the centripetal is but the cyclone theory revised and presented in its true aspect; and although the fallacy of the former is abundantly proved by experience, yet it cannot be denied, that, to the purely theoretical student, it must appear more plausible and more logical than the cyclone theory; inasmuch as it is less difficult to account for the centripetal than the rotary motion of currents of air seeking to arrive at a point of minimum pressure in the center of a storm.
Mr. Redfield and his followers or co-workers have however presented us with a true problem and furnished us a formula for its solution, and the man who at this day runs into the center of a cyclone when he has room to avoid it has no one but himself to blame.
With reference to the case already mentioned as being on record in a work entitled "Storms; their nature classification and laws"—by Professor Blasius, page 241, and which Mr. Meldrum is there represented as citing in support of his theory of inblowing currents in great ocean storms, I have translated from a work entitled : "Etude sur les Ouragans de l'hemisphere Austral," second edition by M. Bridet Capitaine de Fregate, etc. etc. [published under the auspices of the Minister of Marine, issued from the Depot des Cartes et Plans de la Marine. Paris and numbered 465] the following account of the storm of the twenty-sixth of February 1860. Captain Bridet was at the time Captain of the port at Reunion and his account of the storm is from personal observation, the reports of commanders of vessels and from extracts from the logs of forty-two vessels that were involved in the storm.
Thus; on page four he says: "My functions as Captain of the port at Reunion, have enabled me to consult the logs of forty-two vessels, which, either left the roads of the colony, or were in its vicinity at sea; all having suffered more or less during the storm of February, 1860. By data found in these logs I have been able to fix the position of these vessels at noon February twenty-sixth, as well as the winds experienced by them at the same time."
On page 115 and following pages to page 137, 1 find the following account, which I have somewhat abridged in the translation, to suit the purposes of this paper.
"On February 25th 1860 at 9 A. M. the vessels at anchor in the roadstead of St. Denis, received orders from the port authorities to put springs on their cables, slip and stand to sea. A continually falling barometer, a heavy swell (bore) and squalls from the S.E. in short every appearance of the weather indicating a storm approaching.
The vessels in other quarters had been under way for several days, so that, at this moment, all the roadsteads of the colony were abandoned. In getting underway from St. Denis the vessels stood out on the starboard tack close hauled; but the rain, which fell abundantly, soon shut them out from view of some of their commanders who stood on the shore watching the maneuvers of their vessels with a very natural anxiety. What they (the vessels) did after this time, and the perils which they encountered has been learned from the logs or the reports of each one as follows:
The wind was steady from S.E., which indicated that the center of the storm would not pass far from Reunion, and consequently that the vessels at sea would find themselves nearly in its track; therefore,
several of the captains better informed than the rest, or perhaps, having more confidence in the cyclonic theory of storms, did not hesitate to put their ships before the wind in order to cross the storm track in front of the center and take refuge in the manageable semi-circle. Four of them l’Angele, la Somme, l'Alfred (colonial) and la Victorine, adopted this course. (Plate II Fig. 4.)
L’Angele (Captain Barraud) from Saint Lew on the 22nd of February bound for La Possession was the first to decide on this course, and the captain in his report expresses himself as follows : On the 25th of February at ten A. M. being about fifteen miles N.KW. of cape Bernard on the starboard tack, seeing the barometer at 747mm (29.40 in) and still falling, the appearance of the weather bad and getting worse and the wind steady from S.E. I judged that I was on the track of the advancing storm. The sea was not yet very heavy and I decided to scud, according to the storm theory, and filled away without any accident. I ran N.W. under my close reefed main topsail. At 4 P.M. the sea had increased considerably, the rain fell in torrents, and the violence of the wind was much greater. I was then about seventy miles N.W. of St. Denis, and still continued my course under the same sail. My vessel being only half loaded behaved perfectly well in this way."
At 8 P. M., barometer had reached 744mm (29.291 inches) below which point it did not fall.
From this moment the wind and sea commenced to moderate, but I nevertheless continued my course.
Midnight 26th February (25th & 26th) the wind hauled to South, and during the night to S.W. and west, moderating very much. I followed the direction of the wind by scudding, until 10 A. M. on the 26th, at which time, finding myself at a safe distance from the center, I brought the ship to on the starboard tack, with the wind at west; barometer 747mm (29.40 inches.) The wind was still strong, but the sea was less heavy and the vessel did not labor much.
The vessel was kept hove to on the starboard tack until 6.00 A.M. February 27th, when Captain Barraud, seeing the weather almost entirely re-established, decided to profit by the N.W. wind to regain the anchorage.
This vessel arrived at St. Denis, where she called before proceeding to the roadstead of La Possession, her destination, on the 29th of February, without having suffered damage of any kind, not even the loss of a sail; in short, she was in perfect order and ready to proceed to sea immediately.
It is interesting to remark how firm was the confidence on the part of Captain Barraud in the law of storms, which, as we have seen, was well justified.
At 8 P. M. on the 25th he had scudded for ten hours, during which time the wind and sea had increased, the barometer steadily fallen and the weather grown worse and worse. Under such circumstances, must he not stop? Is the law of storms so well established that one may blindly confide in it? And, finally, ought one to continue running seaward when the weather gets worse in proportion as the land is left in the distance?
"Captain Barraud did not hesitate, he knew very well that he was Bearing the center, but he also knew that the wind would soon change and moderate, and that he would rapidly distance the center, so he continued scudding. At 10.00 P. M., he crossed the line of the axis of the storm track, about eighty-five miles from the center, and after midnight the wind veered to S.W. and west, and moderated as he had anticipated. The vessel scudded twelve hours before crossing the trajectory of the storm, and ran from one hundred and twenty to one hundred and thirty miles before reaching the manageable semicircle.
M. Ansart, Lieutenant de Vaisseau, commanding the corvette La Somme had the same confidence in the law of storms and reaped the same benefit. This corvette left St. Denis' roadstead at 9,00 A. M. on the 25th February under sail and steam, and stood out on the starboard tack N.E. carrying storm stay-sails and mizzen. At 2.30 P. M. the commander, seeing the wind blow steadily from S. E. and constantly increasing, the barometer fall and the sea rise higher and higher, thought that by keeping on his course he would pass very near the center, and decided to run off to the N.W. The wind and sea increased steadily during the evening and at midnight the S.E. squalls became intense; barometer had fallen to 744mm (29.29 in.) the rain fell in torrents without intermission and the ship rolled terribly. Still he continued to scud. At 4.00 A. M. on the 26th the barometer had fallen to 742mm (29.21 in.) and the wind was S.S.E. At 6.00 A. M., the wind was S.S.W. and it was evident at this time that the ship had crossed the track of the center. Captain Ansart knowing that he was then in the manageable semicircle, hove his ship to on the starboard tack under the storm-mizzen. The squalls had reached their maximum force, and the rain beat with a violence unheard of. About 11.00 A. M., the sea running very high, the ship took a deep pitch, during which a part of the jib was carried away. The barometer continued falling until noon when it reached its lowest stand 740mm (29.13 in.)
From this moment the barometer began to rise, the sea moderated, and the violence of the wind gradually subsided as it veered to the west and N.W. The following morning, (the 27th) at 8 o'clock, the weather had so far moderated that the corvette set a course for the anchorage at St. Denis where she arrived at noon on the 28th.
From the extract of this Journal (log) it is seen that the corvette, having filled away at 2.30 P. M., did not reach the axis of the storm track until about 3 o'clock the following morning, and that she had run for about twelve and a half hours without any sensible change of wind, and it will be readily admitted that it required a good deal of faith in the law of storms to persevere in the maneuver under these circumstances.
The corvette having started to run later than L’Angele, must have passed nearer the center in crossing the trajectory, and such in effect is the fact, she having passed sixty-seven miles in front of the center at the time of crossing the line of its axis.
Instead of stopping to heave to at 6.00 A. M., it would have been better to have continued scudding for several hours more; the wind being only at S.W. shows clearly that the center was still drawing nearer.
(The storm was travelling W.S.W. 7 miles an hour.)
L'Alfred and La Victorine were the other two vessels that scudded during this storm. These two fared rather worse than the first two, in consequence of their having started to run at a later hour. L'Alfred crossed the track at 10.00 A. M. on the 26th and passed within 45 miles of the center with her barometer marking 736mm (28.98 inches) and La Victorine crossed the track at 3.00 A. M. on the 26th and passed within 35 miles of the center with her barometer standing at 730mm (28.74 inches) but all four arrived safely in the roads after the storm, and without any more serious damage than the loss of a few sails and a couple of boats."
La Lise-et-Berthe, La Ville de Saint Denis, le Pacifique and le Washington are four vessels which, after getting a good offing, hove to on the port tack and rode out the storm. (The proper thing to do.)
L'Eugene et Amelie, le Veaune and l'Ange Gardien, are three vessels that kept their starboard tacks aboard and stood out to sea; were thrown in contact with the center and barely escaped total wreck.
St. Vincent de Paul, le D’Apres and le Meunier, are three vessels that by keeping their starboard tacks aboard were carried into the center, from which they were unable to disengage themselves, and were eventually wrecked on the coast of Madagascar, whither they were carried by the storm.
L'Albert le Grand, le Bryeron and le Courier des Antilles, are three vessels that disappeared and were never heard from.
Captain Bridet gives the names of twenty-five other vessels that by bad maneuvering, got either into or near the center, and sustained more or less damage, amounting in all to 3,368,882 francs, or $660,300.87 with a loss also of eight officers and forty-seven men.
A detailed account of the maneuvering of most of these vessels is also given, but the above is sufficient for my purpose, as I simply wish to show, that Mr. Blasius, in citing this case as proof of the fallacy of the cyclone theory, is all wrong, and that the newspaper article to which he refers was entirely erroneous.
This case to the contrary, owing to the vast amount of reliable data collected from it, furnishes more conclusive proof of the correctness of the cyclone theory than any other case on record; inasmuch as the reports in this case cover every part of the storm disk, and Captain Bridet an educated seaman, interested in the work and on the spot, shows clearly and distinctly, that every Captain who conformed to the rules laid down by Redfield and Reid, escaped unhurt, while those who did not were either totally lost or sustained serious damage; and I will venture to say without depreciation of science, or discourtesy to its devotees, that until the meteorologist shall have solved the whole problem of the storm mystery, and be able to demonstrate satisfactorily the course of the winds within the storm disk, we must depend on the seaman who comes from the Ocean storm center to tell us how the winds blow there; and, until some better system, based upon a more correct knowledge of the storm area, is devised for avoiding the dangerous center, it will scarcely be prudent to discard the time-honored and tried rules of Redfield, Reid, Dove and Piddington. It is pleasant and profitable to discuss these things on shore, but the officer who finds himself in a storm at sea, ought to have a fixed plan of action, lest by argument and experiment he loses valuable time, perhaps, even ship and crew.
From a careful study of the foregoing examples of actual experience, as well as from a great quantity of similar information, both written and unwritten, most of the latter from persons direct from the storm disk, I am convinced, and assert without fear of contradiction or criticism, my belief that the winds within the area of an ocean storm blow in circles or practically so, and that in mid-ocean where there is room to maneuver, the only way to avoid danger or damage is to conform absolutely to the cyclone rules. But, I am also satisfied that in the vicinity of land the storm disk is more or less distorted according to the character of the land, the angle of contact with it, and the rate of forward movement of the storm; and, inasmuch as two of these elements are always uncertain, no rules can be framed for such a case. If however, the angle of contact is small, say less than 20°, although the wind on the side of the storm nearest the land would doubtless draw along the coast, yet the seaward side would probably not be much affected by it, or the winds on that side be sensibly deflected from their normal direction; but if greater than 20°, it may reasonably be expected that the entire storm disk will be distorted in proportion to the resistance offered by the obstructing medium and the consequent check given to the part of the storm nearest to it, which, of course, depends upon the angle of contact and the velocity of the storm. Except in very extreme cases, where the wind would be deflected six or seven points, the variation of the wind from the cyclone point will probably not exceed four points, and if it be remembered that the effect of the flattening in of a cyclone will always be to bring the center nearer the land than the direction of the wind would seem to indicate, the bearing of the center even in such a case might be estimated pretty closely by making allowance for the deviation of the wind.
But wherever there is a doubt on this point there is a corresponding impossibility of discussing the subject intelligently, and the fate of the ship depends after all upon the judgment of the commander.
The latest work (as far as I know) which pretends to deal with cyclones as a specialty, is published by the British Meteorological office, prepared under the direction of Captain Henry Toynbee, Marine Superintendent, London, England, and treats of the North Atlantic storm of August 1873. It is elaborately illustrated by charts and diagrams, constructed from the data of two hundred and eighty ships' logs and a number of shore observations, extending over the entire area of the North Atlantic. These observations have been reduced as nearly as possible to the moment of Oh. 43m. Greenwich time (P. M.) and so plotted on the charts, one of which is prepared for each day of the month, furnishing at a glance information as to the direction of the wind, atmospheric pressure, temperature, &c.
It supposes the formation of a cyclone in the vicinity of Cape de Verde islands on the 12th August, but no perceptible development of cyclonic winds occurs until the 14th when the position of the center is assumed from later observations to have been about 14° N. latitude and 37 ½° W. longitude. The cyclone, from this point, is represented as travelling W.N.W. on a curve trending more northwardly as it nears the West India islands, and still more to the northward after passing St. Thomas, to a point about two hundred miles west of Bermuda; after which it takes a north-easterly course until it strikes the south shores of Newfoundland where it is supposed to have spent itself on the 27th, as no trace of it was found after that date. By projecting a circle with a radius of three hundred miles from the center, as marked each day on the charts, I find that the number of observations obtained within the storm area proper, varies from one to thirty daily, after the 18th when the storm was fully developed, to the 27th when it broke up, in all about eighty-six observations.
From these data Captain Toynbee concludes that the wind, instead of blowing in circles, has a mean in draft of about 29° or in other words that the angle between the direction of the wind and the bearing of the center is about ten and a half points instead of eight points as taught by the cyclone theory. A table on page eighty-nine showing the mean of one hundred observations, gives a mean angle of 119°.
On page 88 is a diagram, (Plate II, Fig. 6), showing the probable course of the wind in the storm disk, plotted from observations on the 25th of August when the position of the center was pretty well known.
On August 23d at11h. 20m. A.M., an American mail steamer (Albemarle) hove to north of the center (distant about two hundred and twenty-five miles by chart) to ascertain the course of the storm, and having laid to for two hours without a change of wind and with a falling barometer (from 29.94 in. to 29.80 in.) the master concluded that he was on the track of an advancing storm, and at 1h. 20m. P.M., started to run N.W. by W. wind E. by S. a little on starboard quarter. At 4h. 40m. P.M., barometer again registered (29.94 in.) wind and sea had moderated and the squalls were less frequent.
From 4h. 40m. P.M. (23d) to 4h. 40m. A.M., (24th) barometer remained steady, during which time as the wind backed to the northward the ship steered W.N.W., West, W.S.W., S.W. and South which course she was steering at 4h. 40m. A. M., at which time the weather was more moderate, without squalls and clearing. After this time she resumed her course S.S.E. ½ E. the barometer rising gradually.
By a glance at the diagram (Fig. 5) it would appear that such a maneuver was not possible, and therefore it may reasonably be supposed that this diagram does not correctly represent the circulation of air in the storm during the 23d and 24th when the Albemarle did perform it.
Again we have a diagram by Dr. Meldrum (Plate II. Fig. 6) which like the above I have roughly copied from page 88 and which is supposed to represent the circulation of air in the Mauritius hurricane of February 25th, 1860, the same as heretofore alluded to at Reunion island. By a glance at the diagram it appears that a vessel running before the wind must inevitably bring up in the center; and yet Captain Bridet in his account of this same cyclone has clearly shown, that four (4) vessels did cross its track running before the wind, one of them within thirty-five miles of the center and all escaped without serious injury. It is not necessary, neither have I time or space in this paper to criticize this work as under other circumstances I might. I will simply say, that, as a purely meteorological work it is doubtless very valuable, but as an expose of the cyclone problem it cannot be classed very high, for the simple reason that the system of simultaneous observations confined to one particular moment of each day as is the case in this instance, is not calculated to give very satisfactory results in this respect, and beyond the fact of showing that a storm actually did pass over or near the track projected on the diagram accompanying the daily charts, it has proved nothing new. The mere fact of a gust of wind rushing wildly toward the center for ten or fifteen minutes, about the time for which the chart is plotted, does not by any means disprove the circular theory. Every seaman who has ever had the responsibility of a ship in a gale at sea, knows very well, how anxiously he has stood on the quarterdeck watching his close-reefed main-topsail and wondering whether it would stand such another flap as the last one, or whether the next would split it into a thousand pieces.
It must be remembered in this connection that the author and advocates of the cyclone theory do not claim that the winds blow absolutely in circles, such as would be formed by steel springs bent into that form; it is well known that certain irregularities in the course of the winds due to local disturbances frequently take place within the storm disk, and Mr. Redfield in the "American Journal of Science and the Arts," second series No. 1, page 14, says: "When in 1830, I first at tempted to establish by direct evidence the rotative character of gales or tempests, I had only to encounter the then prevailing idea of a general rectilinear movement in these winds. Hence I have deemed it sufficient to describe the rotation in general terms, not doubting that on different sides of a rotatory storm as in common rains or sluggish storms, might be found any course of wind, from the rotative to the rectilinear, together with varying conditions as regards clouds and rain.
The common idea of rotation in circles, however, is sufficiently correct for practical purposes and for the construction of diagrams. The degree of vorticular inclination in violent storms must be subject, locally, to great variations ; but it is not probable that, on an average of the different sides, it ever comes near to forty-five degrees from the tangent of a circle, and that such average inclination ever exceeds two points of the compass may well be doubted."
The incurving of the wind and a few isolated irregularities in its course, is all that appears to me to be proved by this investigation of the August storm, and this knowledge, as I have shown, is not new.
There is evidently need of more information on this subject, but it is not attainable by the system of simultaneous observations as now practiced; this I admit will greatly assist the investigation, but if we wish to know what is going on in a storm five hundred miles east of cape Henry, or anywhere else beyond the limits of the signal-service-men on shore, we must send seamen there in ships to find out, and to this end we must educate and interest our merchant-seamen in the work, by instructing them how to observe and how to record their observations.
This work has been inaugurated and is now fairly started by the U. S. Hydrographic office at Washington, D. C, where Journals are prepared in a desirable and convenient form and issued free of charge to any and all seamen who will promise to keep them faithfully and return them to the office when filled. These Journals contain, besides the forms for recording observations, full and complete instructions as to the manner in which they should be kept and are embellished with elaborate illustrations and explanations of the instruments employed in making the observations.
By this method only can we hope to settle the much disputed question of: How the winds blow within the storm disk.
I trust the day is not far distant when this important undertaking shall be crowned with all the success it deserves, and when every seaman, naval as well as merchant, shall feel that he has a special and personal responsibility to meet in connection with this work, and when in consequence, he shall prosecute his researches to the full extent of his opportunity for doing so.
A few years of lively investigation of this kind will make up for lost opportunities in the past and most of us here may reasonably hope to see the final solution of the storm problem, at least that part of it which affects the management of a ship and the manner of avoiding danger.
There are certain other things which might properly come within the scope of this paper, such as cyclones following each other, traveling near each other on parallel tracks or crossing; but all such cases are so fully discussed in all the standard works on storms that it is not necessary here to say anything about them.
The action of the barometer and the indications of a storm as well as the rules for avoiding it are matters of general interest and doubtless familiar to all of us, I will therefore touch but briefly on these points before concluding.
REMARKS ON BAROMETER AND STORM INDICATIONS.
Barometer. The barometer as an instrument of warning, and also an approximate measure of the distance from the center of a cyclone is of vital importance to the seaman.
First. The barometer generally indicates the approach of a storm by a restless oscillating motion of the mercury, caused by a disturbed condition of the atmosphere in the vicinity of a storm and the consequent passage over it of atmospheric waves of different heights. These oscillations have been observed to vary from a just perceptible motion to 0.02 inches.
Second. The barometer often rises suddenly just on the border in front of a storm, by reason of the air banking up there, and therefore, if the clouds and general appearance of the weather indicate the approach of a storm the rise in the barometer, if any occurs, is no guarantee that it will not come, but rather a sign that a severe storm is coming. (The barometer will probably not rise much in front of a slowly moving storm.) Had the captain of the Francis Henty properly interpreted his barometer, he would have remained westward of the islands and kept out of trouble.
Third. A very rapid fall of the barometer after fairly entering the storm disk, may be regarded as evidence of a very violent storm of small diameter, and a gradual fall would indicate the contrary.
Fourth. If a vessel by any accident was caught in a cyclone, situated as the vessel which in a preceding paragraph I have pictured on the east coast of Formosa, the knowledge of her distance from the center would be all important, even if it could not be determined nearer than fifty miles, and to aid navigators in determining probably within that distance, the distance from the center, a table is published in Piddington's Horn book, 3d edition, page 252, which I give here for what it is worth, and which in an extreme case may prove of service.
I have compared the fall of the barometer in a great number of cases with the above and generally found the result very favorable.
The indications of the approach of a cyclone do not differ materially from those of the ordinary gale; but a few such, as a hard steel gray sky or having a greenish tint, a blood red or bright yellow sunset, a heavy swell unaccounted for in any other way, and a thick lurid appearance of the sky, may be regarded in connection with a general threatening appearance of the weather, and particularly with a restless state of the barometer, as significant signs of a more than ordinary gale, and, whether seen separately or together, ought not to be disregarded.
When by any of these signs or by the action of his barometer the navigator has reason to suspect that a cyclone is not far distant, his first care is to devise a plan for avoiding it, and if he knew positively the direction of its course this might sometimes be accomplished. An approximate idea of the storm's movement in certain localities may be had by an inspection of a cyclone chart such as is found in the standard works on storms—but although the cyclone tracks generally lie in the same direction and as a rule not very far apart, probably not more than four or five hundred miles at any given point, yet it does not follow as matter of course that every cyclone travels over the beaten track, and therefore, there is no certainty that the approaching storm will do so. By a knowledge of the tracks in the locality the navigator may, however, try to avoid it, but if after doing his very best to effect this he is still caught in the storm, he must then as quickly as possible determine his position in the storm disk and the course of the storm. This may always be done by a knowledge of the following few, simple facts committed to memory, viz.:
RULES FOR AVOIDING THE CENTER.
Right Semicircle—Wind changes to the right N. E. S. W., heave to on starboard tack.
Left Semicircle—Wind changes to the left N. W. S. E., heave to on port tack.
This is all that is necessary to place the ship in a safe position north or south of the equator until the course of the storm is determined. This may further be reduced to six words, by associating the direction of the change of wind, with the semicircle of the storm and the tack to heave to on—and taking them in this order we would have for the right semicircle: Right Right-Starboard, and for the left semicircle: Left-Left- Port.
In order to simplify the problem as much as possible, I have discarded the terras: Dangerous semicircle and manageable semicircle and substituted right and left semicircles. The right semicircle being that portion of the storm disk situated on the right of the axis of the storm track, looking in the direction of its course, and the left semicircle the portion of the storm disk lying on the left of that line.
ROTATION OF WIND,
Northern hemisphere—from Right to left N. W. S. E., left handed, or, in nautical language, against the sun.
Southern hemisphere—from Left to Right. N. E. S. W., right handed, or, as a sailor would say with the sun.
BEARING OF CENTER.
Northern hemisphere—8 points (90°) to the right of the wind point, looking in the wind's eye.
Southern hemisphere—8 points (90°) to the left of the wind point, looking in the wind's eye.
Two bearings of the center with an interval of from 2 to 3 hours between will in general be sufficient to determine the course of the storm, provided an accurate account has been kept of the ship's way; but if the storm is moving slowly a longer interval may be necessary. There are but two points in the storm disk of a cyclone where a vessel hove to will not experience a change of wind—one is in front of the center on the line of its axis and the other in rear of the center on the same line; for these two cases the barometer must be the guide—in front of the center it falls and in rear of the center it rises.
There are also five points in the storm disk of a cyclone, where a vessel may run along with the storm, parallel to its course, and at equal speed; without having any change of wind, and with a steady barometer.
NORTHERN HEMISPHERE.
1st. In front of the center on the line of its axis. "Wind on starboard beam.
2nd. Anywhere in the right forward quadrant. Wind on starboard side abaft the beam,
3rd, In rear of center on the line of its axis. Wind on port beam.
4th. Any where in the right rear quadrant. Wind on port side abaft the beam.
5th. Abreast and to the right of the center. Wind aft.
SOUTHERN HEMISPHERE.
1st. In front of center on the line of its axis. Wind on port beam.
2nd. Anywhere in the Left forward quadrant. Wind on port side abaft the beam.
3rd. In rear of center, on the line of its axis. Wind on starboard beam.
4th. Anywhere in the left rear quadrant. Wind on starboard side abaft the beam.
5th. Abreast and to the left of center. Wind aft.
The above maneuvers are possible providing sail can be carried, but only three of them are advisable, viz: the position abreast of the center, in the rear quadrant, and in rear of the center. Running along with the storm in front of the center or in the forward quadrants should never be resorted to, as an accident to sails or spars, temporarily disabling the vessel, would at once place her in great danger of being overtaken by the center.
TO RUN OUT OP THE STORM IN THE NORTHERN HEMISPHERE.
Right Semicircle. Haul by the wind on starboard tack and carry sail as long as possible; if obliged to heave to, do so on starboard tack.
Left Semicircle. Bring the wind on starboard quarter. Note the direction of the ship's head and steer that course. If obliged to heave to, do so on port tack.
On the storm track in front of center. Square away and run before it. Note the course and keep it, and trim the yards when the wind draws on the starboard quarter. If, however, obliged to heave to, do so on port tack.
On the storm track in rear of center. Run out with wind on starboard quarter, or leave to on starboard tack.
TO RUN OUT OF THE STORM—SOUTHERN HEMISPHERE.
Right Semicircle. Bring wind on port quarter. Note the course and keep it. If obliged to heave to, do so on starboard tack.
Left Semicircle. Haul by the wind on port lack. Carry sail as long as possible, and if obliged to heave to, do so on port tack.
On the storm track in front of center. Run before it. Note the course and keep it, and trim the yards as the wind gradually hauls on the port quarter. If obliged to heave to, do so on the starboard tack.
On the storm track in rear of center. Run out with the wind on port quarter or heave to on port tack.
A rise in the barometer, improvement of the weather, and a gradual abatement of the force of the wind, will result from the above maneuvers; and the ship should in each case be kept on her course until by these signs it is made evident that she is out of danger.
All the above maneuvers depend of course on sea room, and the ability to carry sail. If sail cannot be carried or land interferes, the ship must be hove to on the starboard tack in the right semicircle, and on the port tack in Left semicircle, and never otherwise. The old popular idea of heaving to on the starboard tack in the northern hemisphere and on the port tack in the southern hemisphere, under all circumstance:, has been revived by a late writer, and is advocated even by some seamen. I strongly protest against this practice as being likely to lead to the destruction of life and property.
It is asserted as a reason for doing so, that a vessel so disposed lies with her head from the center, which is true; but she also lies with her quarter to the sea, even if she is not taken aback and swamped before the wind has headed her off that far. A vessel will not head reach laying to under storm canvas, probably nothing but a storm mizzen, and the suggestion is so un-seamanlike, that I am inclined to believe that those who write on the subject and recommend such a thing are not familiar with the management of a ship in a gale; and, that the seamen who hold such opinions, have not given the case the consideration it deserves; in other words, that they have forgotten all about the sea, in the dread contemplation of the center.
It must be remembered that the wind changes much more rapidly than the sea; and I have laid to in the right semicircle of a cyclone in the southern Indian ocean on the starboard tack, when in the heaviest sea near the end of the storm, the ship was lying nearly head on to the seas. It is not necessary to state here what would have been her position with respect to the sea or the inevitable consequence, had she been on the port tack.
It sometimes occurs, although the cases are very rare, that a cyclone takes a sudden turn, and recurves on its track so much as to render a vessel liable to run into it a second time.
Colonel Reid, in his work on the Law of Storms, (page 173 and following,) recites a remarkable instance of this kind, which occurred in the year 1809, in the Indian ocean, southward of the island of Mauritius, A cyclone was encountered by H. M. S. Culloden, convoying a fleet of the Hon. East India Company's ships, bound homeward, near the twentieth parallel of latitude; at which time the storm was travelling about W.S.W., and after passing over the fleet continued its course until near the twenty-fifth parallel, when it suddenly turned towards the E.S.E., and the fleet steering about S.W., ran into the storm a second time, and several of the ships were lost.
But at that time nothing was known of the Law of Storms, and the popular thing appears to have been to scud before a gale, which some of these vessels did, and were lost in consequence, being in the left semicircle where they ought to have laid to on the port tack, instead of attempting to cross the storm track by scudding.
A similar case occurring at the present day, would be very much simplified, as we can readily locate the center and determine the direction of its movement.
In conclusion I would say: Although my argument has been made in support of, and as far as may be to prove what many will doubtless say has been an established fact for fifty years, (with which opinion I am myself in perfect accord), yet in view of the fact, that efforts have in late years been made to overthrow a system, which, during the same length of time (nearly) has been the only safeguard to navigation as far as concerns ocean storms; and further, that as these efforts have not only failed to stand the test when compared with facts, but have suggested no new or better method by which to insure the safety of a ship at sea, I have thought myself justified in thus occupying your time and trying your patience, and I trust I may not have been mistaken.
The President. I will simply say that I, myself, have had opportunities of verifying the circular theory of hurricanes which is so generally received, I mean the theory of Redfield; and I have, by following the rules laid down by him, avoided storm centers.
When I was first in the East Indies, I gave a great deal of attention to storms. The opinion at which I arrived after much experience and reading on the subject, was in entire conformity with Redfield’s theory. The incidents of the hurricanes themselves were not different from those recorded in books. I acted upon the assumption that Redfield’s theories were right and in practice I found them true. I believe that Espy’s theory is wrong, and will not stand investigation.
Rear-Admiral J.J. Almy. If there are no further remarks on this subject, I move that the thanks of this meeting be tended Lieut. Commander Nelson for the very instructive paper he has read to us this evening.
The motion was carried unanimously.