In the absence of the author, Master S.A. Staunton, U.S. Navy, read the following paper.
Not many months since a Commission, appointed by the President, was in session at Washington to determine the comparative merits of the various ship-canal routes across the Isthmus of Central America. As this Commission was composed of three officers of high rank in their several professions, whatever decision they may have reached may be considered exhaustive and final. The report of General Humphreys, Admiral Ammen, and Captain Patterson shows that the Nicaragua Line is feasible, and that, possessing certain great advantages over all its competitors, it is, in all probability, likely to become the site of the highway between the Atlantic and Pacific.
Since the adjournment of the Commission I have waited in vain for some abler hand than mine to lay before the Institute the results obtained by the survey of Nicaragua, and my only excuse in presenting this paper—written during the intervals of duty on board ship—is the desire of one who was connected with Commander Lull's expedition, to draw to your attention an enterprise which is in the future to become one of great importance to the Navy and to the country at large. By way of introduction, let me offer a short historical sketch of the various expeditions, both public and private, undertaken at Nicaragua.
The question of a passage to the Pacific, through the narrow Isthmian barrier is as old as the discovery of the continent itself, the very commission granted to Columbus surmising that the East Indies was the goal to be reached. In the great navigator's second and third voyages. We find him exploring the gulf of Paria, vainly imagining that he is about to discover the South Sea. In his wake follow a host of adventurers, seeking the "strait." Balboa, Ponce de Leon, Ogeja, Lotes, Pizarro, all—in connection with their other projects—sought to render their names famous by the discovery. Even as late as 1687, we find Sieur de Lussan, a French "Filibusterer" writing:—"This lake (Nicaragua) hems in three islands, that are not far distant the one from the other, and all of them very near the mouth thereof. Some few years since the Hourqua (specie vessel) of Acapulco, that went to the East Indies, on its return, entered in this lake through the bay, and we understood that some Spaniard had entered by the other end of it, through the river Vastaqua that discharges itself into a bay of New Spain and consequently the North Sea."
This account of a ship passing from ocean to ocean is undoubtedly overdrawn, though it is highly probable that the channel of the San Juan or Vastaqua was much deeper, prior to its partial destruction by the Spaniards during the last century.
Dampier's Voyages contain interesting accounts of Nicaragua; while Humboldt, in his "New Spain," after an elaborate description of several routes, states, that "communication with the Pacific ocean would be effected by cutting a canal across the Isthmus, which separates the lake from the gulf of Papagayo."
The first regularly organized expedition to Nicaragua was probably undertaken in 1778, by two Spaniards named Yzasi and Alexandre. They were accompanied by two Englishmen, Hodgson and Lee, who published a description of their work on their return to England. This survey was supplemented by an examination of the territory west of Lake Nicaragua, conducted by a government engineer named Manuel Galisteo, in 1781.
In 1825, De Witt Clinton endeavored to arouse the interest of the United States to the importance of ship communication between the two oceans; though it was not till ten years later that President Jackson appointed an agent to examine the Isthmus, and then the objective point was Darien and not Nicaragua.
Mr. Bailey, a retired officer of the British Navy, was employed in 1838, by the government of Central America, to make a survey of this canal route. His operations were confined to the territory between the Lake and the Pacific, and were consequently incomplete.
During the next few years several companies were formed in Europe, nominally for the colonization of the Isthmus, but actually as preliminary steps towards a future canal. But one of these companies commanded much attention, and that simply from the romantic interest attached to the man at its head. A political prisoner, confined in the fortress of Ham, and shut out from the hope of ever attaining the crown of France, conceived the idea of perpetuating in America the glory of a name already famous the world round. He entered into correspondence with Senor Castellon, the minister of the Central American government at the Court of Louis Philippe, reviewed with singular ability the various canal schemes, and offered, if released from confinement, to superintend in person the work at Nicaragua. In 1840 the princely prisoner was liberated, and, going to England, published—under the initials, "L.B."—a pamphlet, setting forth all the arguments in favor of a canal, and adding the official proceedings by which the government of Nicaragua had vested in him full power to form a company in Europe. The canal was to be "Canale Napoleon de Nicaragua." The late prisoner was Prince Louis Bonaparte.
The discovery of gold in California gave a fresh impetus to the question. As the new state increased in population, and San Francisco became a large city, the necessity of a highway between the Atlantic and Pacific was again urged. The voyage around Cape Horn was long and dangerous; the overland route, across the Plains, subject to attack from Indians; something must be done to avoid both; the settlers on the western coast needed the provisions of the eastern ports; the merchants of the old states, the gold of the new.
As the result of these arguments, "The Atlantic and Pacific Ship Canal Company" was formed, with Commodore Vanderbilt for its president. A.W. Childs, a prominent civil engineer, was sent to survey the lakes and rivers of Nicaragua. His party was in the field from August, 1850, to September, 18pl, and returned to the United States with a very favorable report as to the feasibility of the project. Funds for its accomplishment were not, however, forthcoming and Childs carried his estimates and maps to England, where they were submitted to a commission of engineers, and afterwards to a committee of capitalists, who, though favoring the route, did not judge the plan sufficiently well developed to merit their support. The canal enterprise must have been considerably agitated about this time, for a convention was made between Great Britain and the United States, in which Mr. Clayton on our part, and Sir Henry Lytton Bulwer on theirs, "define the principles which should apply to an inter-oceanic canal wherever and whenever constructed."
In 1855, Walker's filibustering expedition again drew the attention of the public to the State of Nicaragua; but the "gray-eyed man of destiny," succeeded only in making the inhabitants of the Isthmus look with mistrust upon any so called explorations or surveys.
Ten years later P.C.F. West was employed by the Central American Transit Company, and although his object was simply to devise means for the improvement of the San Juan, and the restoration of Greytown harbor, the maps which were made of that locality have been of value to the late expeditions, as they show the gradual changes taking place during the years that the harbor of San Juan del Norte has been closing.
The first regularly organized expedition sent to Nicaragua by the government, left the United States in the spring of 1872. We all remember who was at its head, and how Grossman and Force found a watery grave amid the surf and breakers at Greytown beach. The command then devolved upon Commander Hatfield. The dry season was half over before the work fairly began; but, by the energy of the officers, three lines on the western side of the lake were partially examined. With the month of July came the rainy weather, and the party returned to the United States to be completely fitted out for the ensuing winter.
On the 3d of December, 1872, the second expedition, consisting of eleven naval officers, four civilians and a force of about thirty men, sailed from Fortress Monroe in the "Kansas."
I would now ask your attention for a short time to the results obtained by Commander Lull and his officers, during the five months that the expedition was on the Isthmus. The discussion of a Canal through Nicaragua naturally divides itself into three distinct parts; viz. The Lake; the Western Division; and the Eastern Division.
The Lake. It is a generally received idea that there is a range of mountains extending the entire length of the Isthmus, forming a complete barrier, through which it would be impossible to excavate or tunnel.
That the Cordilleras do certainly exist in one continuous chain is undoubtedly true, but at one point they sink to low elevations, becoming simply bills which skirt the Pacific shore. But as the mountains lose their altitude, the valleys to the eastward gain in depth, forming a basin into which the volcanoes of Costa Rica and Nicaragua pour the vast amount of waters which drain from their lofty sides.
This basin is known as the Lake of Nicaragua or Granada. It covers an area one hundred miles long by forty broad; is in places over one hundred fathoms deep; contains a channel, from its eastern to its western extremity, capable of floating the largest ships; is only one hundred feet above the ocean; and by reason of its magnitude, is subject to none of those extreme changes of level so common in all small bodies of water situated in the Tropics.
The distance of the lake from the Atlantic, in a straight line, is seventy miles, from the Pacific only ten; its outlet is the San Juan river, which flows from the S.E. extremity, and after many sinuosities reaches the Atlantic at a point one hundred and eighteen miles from the lake.
Here then, we have a reservoir capable of supplying a uniform and inexhaustible amount of water; the gauges of the San Juan showing a flow of over nine hundred million cubic feet per day; whereas the demand could never exceed a thirtieth of that quantity.
Over and above these advantages there is another of great importance. The lake divides the canal into two distinct sections; and, consequently eliminates any danger from a "block;" vessels being locked directly up to the lake where they can remain quietly at anchor, in fresh water, loading under the lee of the numerous islands, with the products of the country, repairing any damages with timber of the best quality, or provisioning for the coming ocean voyage.
The lake is then the great port, and in considering the question of harbors at either terminus it will be well to remember that they can be limited in size to the accommodation of the few ships which may daily arrive. This is especially true for the Pacific Division, for if the weather prove inclement, the out-going vessels can remain in the lake, and be locked down the sixteen miles whenever desirable.
The Western Division. The portion of the survey which it was anticipated would prove the most difficult of a practical engineering solution, was the narrow belt of land between lake Nicaragua and the Pacific. "Childs' route" was said to be the best, but on the arrival of the expedition every landholder in the Rivas Department whose property was adjacent to any seemingly low pass presented a claim for a tentative line. From the numerous applications the commanding officer selected the Ochomogo, the Gil-Gonzales, the Lajas, and the Virgen routes as the most likely to prove satisfactory.
As much had been written concerning the merits of the so called "Napoleonic route"—via lake Managua—the difference of level between that body of water and lake Nicaragua was also determined and the land contiguous to the former lake thoroughly examined; the results showing 22.5 feet between the water surfaces of the lakes, and a soil near Kealejo so porous that an artificial lining would be required to retain the waters of any canal constructed in that vicinity. These disadvantages coupled with the liability of volcanic disturbances, and the lack of sufficient depth to the northern lake, showed the utter impracticability of Napoleon's scheme.
Of the Ochomogo, Gil-Gonzales, and Virgen surveys little need be said; the passes proved to be much loftier than had been anticipated, while the country leading up to them was far from favorable. They were all thoroughly surveyed, however, and only abandoned after numerous offsets had furnished a complete map of the adjoining land.
While the work had been progressing on the above mentioned lines, a party had also been in the field in the neighborhood of Rivas, examining the valley of the Lajas, and endeavoring to improve Childs' survey, by locating a route along a stream called the Rio-del-Medio. We will not follow the party through the vicissitudes of their camp life in this region.
Let us suppose the last stake driven, the last station on the Pacific reached, and then stand at the summit of the Rio-del-Medio line at Jesus-Maria. Turning to the north-east, we see lying before us a gentle slope of nearly six miles, highly cultivated, dotted with haciendas, and checkered with a network of well made roads. To the right are the large indigo fields, with their substantial vats, constructed of the best lime—quantities of which are at hand ready for the canal builder. To the left is the large town of Rivas, surrounded by its beautiful cacao plantations; while stretching to the northward for one hundred miles, and sweeping twelve leagues to the eastward, is the great lake with its cloud-capped, conical island, Ometopec, rising five thousand feet above the water horizon.
If we now turn to the westward, and follow the Medio line along a small ravine, we will find, at a distance of eight miles from the lake, a river flowing towards the east; this is the Lajas, which was surveyed with great care. The summit level of its heel was found to be only forty-four feet above the lake, but the Medio line was preferred notwithstanding its additional excavation; the tortuous course of the former stream, and its narrow, deep channel presenting many dangers during the rainy season. Halting therefore at Las Serdas—instead of following the Lajas—we note that the two lines here become identical and descending through a densely wooded territory reach the Pacific at Brito, sixteen and thirty-three hundredths miles from the lake.
It would occupy too much time and space to go into all the details of the Western Division—details which will be found thoroughly amplified by Mr. Menocal in Commander Lull's Report. It has been seen that the section from the water shed, eastward, is a gentle slope, over well cultivated laud, possessing means of transportation, as well as resources for subsisting the force that may be required for canal purposes. The height of the summit level is only one hundred and thirty four feet above the lake level; add to this twenty-six feet, the depth of the canal, and we have one hundred and sixty feet as the "cut" to be made through the Isthmus at Nicaragua, An excavation which certainly seems insignificant. This low summit level, being also so near the lake, leaves ample space for the development of the ten locks necessary to reach the Pacific, while the sui-face of the canal will, for the western slope, be on the average above the present profile—advantages to which it is sufficient only to allude. No large stream interferes materially with the canal, and the valleys are extended enough to give sufficient room for handling and depositing the material excavated.
Brito, the Pacific terminus of the canal, is a town and harbor only in name, the full force of the sea breaking upon a low sand beach, which terminates near the canal-exit in a tall cliff of indurated clay about two hundred and fifty feet high. At the foot of this cliff is a slight indentation of the coast where the Rio Grande empties. The land adjacent to this river is awash at low water for a distance inland of about half a mile. The intention is to dig out this loose sand, dredge the Rio Grande, and throw a break-water out from the base of the cliff to protect the harbor from the S.W. swell. All this will necessitate no little expense, the rise and fall of the tide, (nine feet), bringing an element into the problem, which greatly increases the estimates.
The Eastern Division. The work on the Eastern Division actually begins about six and a half miles from the fortress of San Carlos; the combined action of the tributary river Frio, and the drain of the San Juan towards the south-east, having formed a bar which will have to be dredged to a depth of ten feet to form a channel of twenty-six. This bar has been gradually depositing for centuries, and is composed of a stratum of alluvial matter ten feet in thickness, underlying which is a bottom of hard clay. The outlay in this locality will however be trivial, the lake steamers even now being able to enter the San Juan, through the soft mud.
Here I would say a word as to the system proposed for this Division. As was before stated, the country for a large distance around lake Nicaragua is drained into that body of water, thus making the river San Juan, for the greater part of its course simply an outlet, free from the remarkable changes of level so observable in tropical regions. Dams can therefore be erected along the river without fear of demolition by the freshets of the rainy season. The valley is moreover enclosed by hills sufficiently high to prevent the stream from finding any other course, even if its surface were raised considerably above its present plane.
These facts have been utilized, and slack water navigation effected by a series of dams—four in number.
The first dam is placed at Castillo rapids, thirty seven miles from San Carlos, the water being raised eighteen feet, and becoming the summit level, or one hundred and seven feet above mean high tide. This elevation is also the extreme high water mark attained by the lake.
The two dams below Castillo, at Balas and Machuca rapids, could be of almost any desired height, as the river is here bordered with hills which at places attain considerable elevation; the water surface is to be raised 22.8 and 26.8 feet at each respectively.
The river, scarcely five hundred feet broad, runs for the next eighteen miles, through a narrow, tortuous valley and winds about the base of precipitous volcanic hills. The channel is from eighteen to ninety feet in depth—a canal ready in fact for the average ship. This region abounds with timber of the best quality, while a few miles back whole forests of the hule, or rubber tree are found.
At the foot of this section, called by the natives Agua Muerte, on account of its dead still waters, the last dam is placed, the water passing over the crest at an elevation of 23.8 feet above the present surface.
Around each of the dams there will be a short canal with a lock of 10.3 feet lift.
Below the Agua Muerte, the whole aspect of the country changes, the San Juan becoming broad and full of shoals and sand, brought down by the river San Carlos from the interior of Costa Rica. The canal proper here begins, and, leaving the San Juan with all its silt and detritus, cuts straight across the lowland for Greytown harbor, reaching the ocean level at a distance of forty one miles from the last dam. There are seven locks between slack water navigation and the Atlantic, all of them located in rocky spurs which could not be avoided and were consequently turned to profitable account, the stone being suitable for foundations. The profile in this section was much better than had been expected; the mean excavation for the whole distance being less than two feet above the water-surface of the canal.
At a distance of seven and a half miles from Greytown the ground has a sharp fall of twenty feet, which brings it to the sea level, and the line to the borders of the first, or Silico, lagoon. Between this point and Greytown there is a system of lagoons, separated from one another by narrow marshes and connected by channels through which the tide ebbs and flows: These lagoons average from twelve to fourteen feet in depth, and have evidently been formed by the same causes which are now operating to close the outer harbor. The opening of a canal, deep enough for sea-going vessels, consequently here reduces itself to a question of dredging the alluvial matter and sand which form the bottom of these waters.
We now come to the last and most important feature of the survey.
Greytown Harbor, can it be restored? This problem is one of such magnitude, that a thorough discussion of the merits and demerits of the several plans proposed would lead these pages far beyond their proper limits; while modesty alone should make the young naval officer exceedingly chary of opposing the views of older and more experienced men. I will therefore confine myself to a few important points concerning the topography of the neighborhood.
It may be noticed that a small stream, called the San Juanillo, leaves the left bank of the San Juan about twenty six miles above Greytown. This small stream was undoubtedly, in time gone by, the main outlet; it flowed (as it does now during the midsummer freshets) into Silico lagoon, and in course of time pushed out, one beyond the other, the successive harbors mentioned above.
At last came an unusual amount of detritus from the San Carlos, which choked the San Juanillo exit, and diverted the whole mass of lake and river water over the low land to the southward. Then the lagoons closed and a new system began, only to end in our own day in the same results; thus, during the past ten years, Leaf's island, at the bifurcation of the lower San Juan and the Colorado, has been completely washed away, and, in 1873, ninety per cent, of the river flowed through the Colorado mouth, emptying into the ocean twenty miles below Greytown, where the lagoon process is again repeating itself.
The conclusion naturally is, that the San Juan, instead of serving to keep open the harbor of "San Juan-del-Norte," has, on the contrary, been the cause of its destruction; and the mouth of the earth-bearing river being now at a safe distance we have only to deal with the known amount of sand between the town and the Caribbean.
But is the coast current not adding to this amount? No, for we find the anchorage a mile outside to be clay and coral, while the specimens from the beach to the southward show that the light volcanic matter from the mouth of the Colorado is not set up the coast toward Greytown. To further prove that there is no motion of translation, and that the shifting of the bar is entirely local, the shores of the bay at Monkey point, thirty miles to the northward, are formed of a deposit which has evidently been long subject to the action of sea water.
Assuming then that the sand in the vicinity of Greytown harbor is a known quantity, neither increasing nor diminishing, the first step should be to endeavor to fix the inner portion, above water, by planting trees, which in a few years would render the whole of Harbor Head and Point Arenas solid and permanent.
The cost attending such an attempt would be slight, and the rapidity with which vegetation grows in the tropics would soon change the low mangrove bushes, which already cover the greater portion of the beach, into a large, deeply rooted forest.
It will be a more difficult matter to hold the sand now under water in place; for the N.W. current and easterly swell are continually setting the bar to the westward and towards the bight where the river channel formerly existed. To counteract this effect it is proposed to construct a break-water, to the eastward of what is known on the charts as Point Arenas.
Short jetties are to be thrown out at right angles to this break-water to receive any accumulation of sand and prevent it from drifting round the end and closing the channel beyond. Whether this plan is feasible or not is a moot-point; as it is also an open question whether or not the action of the ocean would not ultimately form a shoal still further to seaward, and off the end of the break-water. Such action would however, be necessarily slow, the jetties taking up the greater part of the sand composing the bar, and the water from the canal making a clean current, more or less effective against the encroachments of the sea.
Having thus followed the Nicaragua route from ocean to ocean, I will not dwell upon the financial view of trans-continental communication, nor enter into the commercial advantages to be derived from a ship channel through the isthmus; both of which were so thoroughly discussed in Lieut. Collins' very able paper on Darien and Atrato. The certain growth of our mercantile marine, and the necessity of avoiding the length and perils of Cape Horn navigation will ultimately decide that $66,000,000 is a small price to pay for the incalculable advantages to be derived from the new route. Let us hope, therefore, that the "secret of the strait," so diligently sought by the bold navigators of the past centuries, may in this nineteenth be discovered at last by the energy and science of the American people.