COMPRESSED AIR SYSTEM ON THE U. S. MONITOR TERROR.
The use of compressed air as a motive power on board a war-ship presents several advantages over steam or hydraulic power, which render it a powerful competitor. As compared with steam, it is less dangerous, especially during an action, when a broken steam pipe might prove terribly fatal, and it enables certain parts of the ship to be kept at an even temperature, which would otherwise be rendered uncomfortably hot by the presence of steam piping. Steam and hydraulic engines, moreover, require exhaust pipes discharging outside the hull of the ship; whereas the exhaust from the pneumatic cylinders may be turned into the ship or into the outside air, as may be most convenient There are certain localities in a ship where the exhaust from a pneumatic engine would prove a valuable source of ventilation, as, for instance, in a turret crowded with men and machinery, or in the close confinement of a steering room situated below the protective deck. As compared with hydraulic power, the compressed air system is cleaner and more convenient, and free from the discomfort that arises from the leaking of hydraulic pipes and cylinders. There is immunity from freezing. Leakage is not attended with increase of temperature, as with steam; or flooding of the compartment, as with the hydraulic system. There is less danger of break-downs when starting up or stopping motors suddenly than in the other systems.
The U. S. Monitor Terror is the first vessel to be equipped with pneumatic steering engines and pneumatic operation of turrets. The recent tests were highly satisfactory.
The air for driving the various pneumatic devices is compressed by two separate engines, one being placed in the hold near the forward turret and the other near the after turret on the berth deck. The working pressure is 125 pounds per square inch, and there is no reservoir for the air except an eight-inch pipe, which runs through the vessel and supplies the two turrets and also the steering device in the steering room at the extreme after end of the ship. These two engines supply sufficient air for turning the turrets, elevating the guns, lifting the ammunition into the cages, raising the cages to the breech of the gun, ramming home the charge, closing the breech, checking the recoil, and lastly, and most important operation of all, steering the ship itself.
The two turning engines are placed upon the floor of the turret, one on each side of the big guns. Each engine has two cylinders, 8 inches in diameter by 14 inches stroke. A worm on the crank shaft operates a set of gears by which the power is multiplied many times over before it reaches a driving pinion, which, in common with the engine and gears, is firmly bolted to the framing of the turret and of course turns with it.
The pinion meshes with a large circular rack which is bolted to the deck of the ship and lies immediately within the circular steel track upon which the turret rotates. The engines are controlled by suitable levers and hand wheels situated within easy reach of the officer in the sighting hood, the latter being placed over and between the guns.
The elevation and depression of the gun is effected by means of a massive ram, which is hinged to the floor of the turret and bears against a shoe on the under side of the gun carriage near the breech of the gun. On each side of the turret is a cylinder containing glycerine and water, a portion of which, when the gun is to be elevated, is forced by compressed air into the ram, the supply being regulated by valves which are operated by means of levers in the sighting station above mentioned.
Immediately below the turret is the handling room, adjoining which are the magazine and the shell rooms, with which it communicates through doorways which, when not in use, are closed by water-tight doors. Directly below the center of the turiet is a pneumatic loading machine, which rotates upon a vertical shaft, and may be swung to the right or left as desired. The 500-pound shell and the cartridge, the latter in two parts, are run out from their respective rooms on an overhead trolley and placed in the tray of the loading machine. The tray is pivotally attached to the body of the machine by a set of parallel rods and a lever which carries at its inner end a circular rack. Above the rack is an air cylinder whose piston rod terminates in a vertical rack which engages the circular rack before mentioned. By admitting air at the top of the cylinder, the tray with its load is raised to the required height and the latter is placed in the pockets of the loading car.
There are two of these cars, one for each gun, and they travel upon two vertical hoists or trackways which lead up to the breech of the guns. The hoisting is done by two pneumatic cylinders located on the floor of the turret between the guns. Attached to each piston rod and beneath each cylinder is a set of multiplying sheaves. Over these passes a wire rope, one end of which is fastened to the floor of the turret, the other end being carried to the loading car. The speed of the rope is so adjusted that the full stroke of the pistons will serve to hoist the loading car from the floor of the handling room to the breech of the gun. The loading car contains three parallel pockets, which rotate within the frame of the car, friction wheels being interposed to facilitate the movement. One of the pockets carries the shell and the other two the powder charge. The car is automatically brought to a stop with the lowest pocket containing the shell immediately in line with the breech of the gun.
It is then pushed home by a telescopic rammer which is operated by compressed air, the valve which admits the air being worked by a man who sits astride of the cylinder. The rammer is carried by a bracket bolted to an extension of the gun carriage, and it is consequently held at all times in true line with the bore of the gun. After the shell has been rammed home, the loading car is rotated and the two sections of the powder cartridge are brought successively opposite the breech and pushed home. The breech plug is then swung round, thrust into place and locked.
The recoil of the gun is controlled by two pneumatic cylinders, 14 inches in diameter and 40 inches in length. The cylinders are secured to the gun carriage and the pistons to the gun. Before firing, the pressure on the recoil side of the pistons is about 500 pounds per square inch. As the gun recoils, carrying the pistons with it, this pressure is rapidly increased by compression. To reduce the pressure at the end of the recoil, a tapered rod is provided, which passes through the center of the piston and allows the air to pass more and more freely to the counter side of the piston as the gun returns. The residual pressure is utilized to return the gun to its firing position. Perhaps there is no part of the many operations performed by compressed air on the Terror in which the power shows to better advantage—the elasticity of the air preventing all shock and providing an easy cushion in the recoil and counter recoil.
The last and most important duty performed by the compressed air is that of steering the ship. The work is performed by two long horizontal cylinders arranged one on each side of the tiller. They are provided with a common piston rod, in the center of which is a hollow crosshead in which the tiller is free to slide as it is swung right or left by the movement of the pistons. Compressed air is admitted to the outer ends of the cylinders by means of a D valve, the air being simultaneously admitted at the back of one piston and exhausted from the other, according as the helm is to be put over to port or to starboard. Air is also admitted at all times at the inner ends of the cylinders, and a pipe connects them, so that as the pistons move, the air may flow freely from the inner end of one cylinder to the inner end of the other. In the center of the connecting pipe is a bypass valve, which is open when the tiller is being moved, but closes when it has been traversed the desired angle and holds the air imprisoned in the cylinders, thus locking the tiller between two elastic cushions. The heavy shocks to which the tiller is subject in rough weather will thus be received and absorbed by the air, and the framing of the ship will be proportionately relieved of the strain.
Provision is also made for steering the ship by electricity or by hand power. For the latter purpose an auxiliary tiller, which can be quickly coupled to the rudder head, is placed above the pneumatic cylinders. It is operated by means of an endless wire rope which passes through sheaves at the end of the tiller and round a drum attached to the deck beams overhead. The drum is controlled through a chain and sprocket gear by a large hand steering wheel shown in the engraving. The steering may also be controlled by an electric motor which is located in the same compartment. The shaft which operates the valve of the pneumatic cylinders has three clutches upon it, by manipulation of which the steering may be carried on by electrical connections from the pilot house or from either of the turrets. During the tests of last November the rudder was turned from hard a-port to hard a-starboard in the very short time of six seconds. In testing the turret engines, the air was exhausted from the receiver and the compressor was started. In a few seconds the 250-ton turret began to move, and in 45 seconds the full working pressure of 125 pounds to the square inch was realized. It took 52 seconds to swing both turrets completely around their full arc of training.—Scientific American.
LUBRICATING SHIPS’ BOTTOMS TO INCREASE SPEED AND PREVENT FOULING.
The invention of a simple and inexpensive device for accelerating the speed of ships and preventing barnacles and corrosion has recently been brought to the attention of the Chief of Construction and other officials of the Navy Department in Washington.
The invention consists of a mechanism which envelops the submerged portion of a ship with a film of oil, thus reducing friction and overcoming to a large degree the resistance of the water.
A series of iron flanges are fastened along the bottom and sides of the ship below the water-line, in which are inserted sheets of woven wire netting, lathing or sheet iron, covered with an absorbent composition saturated with oil. The flanges have a semicircular covering on top, below which runs a finely perforated pipe which ejects a fine spray of oil against the inside of the flange and on to the sheets, from which it spreads downward.
The oil is not carried away by the water, but through capillary attraction is spread, thus keeping the ship’s hull greased without any waste of oil. It is said that the composition is a perfect carrier of oil under the surface of the water, a feature which has never before been achieved and which will make oil perform below the water-line the same service that it does in quelling a rough sea.
It is said for the invention that, applied to any vessel, either steam or sailing, it will increase the speed by at least twenty-five per cent, without augmenting the amount of machinery or the expenditure of fuel. Another and most valuable feature claimed is that it will prevent the growth of barnacles. These enemies to ships’ hulls aecessitate frequent dry-docking and scraping, at large cost.
The inventor also declares that the fatty composition will completely prevent corrosion of hulls.
The oil used is crude petroleum, and is supplied to the pipes by tanks and valves located above the water-line. The system is so arranged that in rough weather a large quantity of oil can be discharged along the sides of the ship and distributed over the surface of the water, thus providing a more effective method of greasing and smoothing high seas than any yet devised.
The covering composition is an oleaginous preparation of tallow, calcined carbon and several other ingredients which the inventor keeps secret. It is said that it hardens in the water and cannot wash off, and can be applied to submarine war projectiles, permitting double velocity.
The inventor is Rudolf Altschul, a civil and mechanical engineer of New York City.
THE MIKLASCHEWSKI SIGNAL LANTERN.
These lanterns recently were put to a series of practical tests in squadron signaling. The lanterns, or rather the signals made by them, were visible at a distance of 34 nautical miles (60 versts), a distance not before attained by any lamps. The lanterns are very compact, and not large, weighing about 7 lbs. They are filled with alcohol and two kinds of powder, one of them green, the other red, secrets of the inventor. Colonel Mikla- schewski. Attached to the lantern are two small rubber tubes with pear- shaped bulbs. Pressing these bulbs produces flares-of red or green light. A glass hood is fitted to prevent extinguishing by heavy wind or rain. The powder is not affected by moisture; it was as good as dry after having been immersed in a glass of water for some little time. The storing of the powder is not dangerous. Colonel Miklaschewski claims that with his lanterns, signals can be sent a distance of 100 versts, the visibility being increased by the attachment of a mirrored reflector to the lamp. The powder must be sifted before using. The light being very bright, it is recommended that the signal crew wear smoked glasses or turn their backs to the lantern while signaling. The lantern has been introduced into the army telegraph parks, the cavalry, fortresses and boundary guards.—Kronstadtski Wiastnik.
NEW REGULATIONS FOR ENTRY OF ENGLISH NAVAL CADETS.
In pursuance of the decision of the Lords Commissioners of the Admiralty gradually to raise the age for the entry of naval cadets and to shorten to some extent the period of training on board Her Majesty’s ship Britannia, the following arrangements will come into force from the 1st of January: Cadets will be entered three times a year instead of twice as hitherto. The appointments will be dated from January 15, May 15, and September 15 in each year. The limits of age on each of these dates in the year 1897 will be: On January 15 and May 15, 13½ to 15½ years; on September 15, 13¾ to 15¼ years. For the entry on January 15, 1898, the limits will be 14 to 15½. The limits of ages are raised gradually in order to avoid the undesirable result of cadets newly entered being older than the boys already on the Britannia entered in previous terms. There are to be three terms of about thirteen weeks in each year, to commence and terminate approximately as follows: January 14th to April 14th, May 5th to August 5th, September 16th to December 16th. The period of training on the Britannia will extend over four terms, and the examinations will be held about six weeks before the commencement of each term. The examination for the entries to be made next May and September will be conducted on the same lines as heretofore. A notification will shortly be made public as to subsequent examinations. The period of service as naval cadet afloat is to be eight months, and eight months is to be the maximum time that can be gained on passing out of the Britannia. Arrangements will be made to regulate the seniority of officers now on the Britannia who may be placed at any disadvantage owing to the introduction of these changes.
THE USE OF HOMING PIGEONS IN THE ITALIAN NAVY.
[Translated by Prof. Henri Marion, from the Revue Maritime.]
On the 19th of July last, 133 messenger pigeons were liberated from the torpedo-boat J. S. S., which had been designated especially for this service, at a distance of 200 km. from Spezia. The experiment was entirely successful and not a single bird was lost. The total distance was covered in 2 h. 52 m., at an average speed of 60 km. per hour. The same torpedo-boat left again Spezia on the 20th of July with 100 pigeons. After having spent the night at the island of Giametri, these pigeons were liberated at 5 A. M. at a distance of 250 km. from the Spezia loft At 9.20 the first batch of pigeons reached their destination, and were soon followed by the others, without the loss of a single bird. The average speed made was 57,690 m. per hour.—Revista Nautica.
This year, during the Italian naval manoeuvres, a special messenger pigeon service was established, with headquarters on board the Sicilia, flagship of the green fleet, in charge of a lieutenant of engineers of the royal army. Additional cotes were placed on board the Savoia and Umberta, flagships of the yellow fleet, in charge of non-commissioned officers of the army, assisted by some petty officers. There were, all told, 83 pigeons. Four liberations took place, one from the Sicilia at Maddalena, with returns at Rome 15 hours afterwards; another from the Sicilia between Capraia and Vado, and two from the Savoia between the island of Elba and Monte Argentero. This service proved entirely successful.— Italia Marinera.
SEARCH LIGHTS IN COAST DEFENSE.
With the object of applying a practical test to the value of search lights as a protection to the entrances to Plymouth Sound, a series of experiments have lately been carried out in which the military forces had the assistance of the torpedo flotilla attached to the port. For some time past the officers connected with the Submarine Mining Establishment of the Royal Engineers at Elphinstone Barracks, Plymouth, have been giving their attention to the distribution of a system of electric lights arranged so as to cover the two approaches to the port of Plymouth and the entrance to the Hamaoze. Previous to these experiments no actual test of the scheme had taken place, and it is hoped to obtain some reliable data as to the efficient working of the scheme, and also whether it is capable of being improved. Owing to the experiments and the arrangements connected therewith being confidential, it is impossible to give any official details; but from observation and other sources, a good deal has been gathered with reference to the experiments, to which considerable importance is attached. The torpedo-boat destroyers Skate, Ferret, Lynx, Opossum, and Sunfish left Devonport about 4.30 P. M. for Plymouth Sound, with the object of returning to the harbor by passing through the areas defended by two of the powerful lights at Picklecombe and Garden Battery under Mount Edgecumbe. The Royal Engineers and Royal Artillery furnished observers at Drake’s Island, the Breakwater Fort, Penlee Point, the Redoubt, Maker, Bovisand, Staddon, and some of the other defenses, for the purpose of taking rapid and accurate observations of the movements of the torpedo-boats. The experiments the first night were limited to the western entrance of the sound and harbor, and witnessed from a good point of vantage, they were to all appearances most successful. The lights at Garden Battery commanded the whole of the waters of the sound as far as Drake’s Island, and notwithstanding the weather was of the worst description for experiments of this kind, it was possible from the shore to discern small objects afloat. As the destroyers came within range of the defined area they were at first only faintly visible, but as they approached the fierce light which beat upon them from the Garden Battery, they were distinctly seen from stem to stern, and in actual warfare no difficulty would have been experienced in disabling them from one or more of the numerous defenses guarding the western side of the fortress. In continuation of the recent experiments at Plymouth, a trial on a smaller scale was also made at the Needles, when the destroyers Daring and Starfish were employed, with instructions to rush past the Cliff End batteries on the Isle of Wight side and the Hurst Castle fortifications on the mainland, the channel being little more than half a mile wide. So strong was the glare of the light that for a distance of three or four miles the lookout was practically blinded, and it was only by intimate knowledge of the locality that it was possible to steer the vessels past buoys and other obstructions. The vessels were under orders to first pass the lights and to make a dash on Portsmouth; the gunners in the forts opened fire on the boats the moment they came within observation. The Daring shot past the forts unobserved, and the artillery officer in command has since inquired how it was done, as the Starfish was under fire for three minutes and three-quarters. Now in going out to sea the vessels steamed at 18 knots, four cables apart, and, assuming they adhered to this formation, there would have been no difficulty in detecting them. The Daring extinguished her bow lights, and put on full speed, so that she passed the forts before she was expected, and, having no lights, eluded suspicion. The experiment, small in itself, is not without importance. If the raiding boat is only to make a rush at the moment she is expected, there is small chance of her success; but in this instance, by putting out her lights and anticipating expectation by a few minutes, the Daring evaded the watch. It is uncomfortable to think that the Daring did precisely what an enemy would do and that she was successful. —Journal Royal United Service Institution.
TESTS OF ARMOR AND SHELL.
United States.
A test of Carnegie armor was made at Indian Head grounds on March 18. A plate, tapering from 16½ inches at the top to 9½ inches at the bottom, representing a group of side armor of 600 tons for the battleships Kearsarge and Kentucky, safely resisted the impacts of two 10-inch shells delivered with high velocities, and this without cracking or permitting penetration of the projectiles to any appreciable depth. Upon the showing thus made, Capt. W. T. Sampson recommended to the Secretary that the group be accepted. The plate was supported by an oak backing 36 inches in thickness. Two projectiles manufactured by the Wheeler- Sterling Company were employed. The first projectile, weighing 500 pounds, struck the plate at a point three and one-half calibers from the bottom and seven calibers from the end, the thickness of the metal being 12 1-10 inches. The point of the projectile penetrated three inches, and then broke, the base falling in fragments at the foot of the target. The velocity employed was 1340 feet per second. The second shell also weighed 500 pounds, and it was fired for penetration at a high velocity. The point of impact was located three and a half calibers from the top of the plate and an equal distance from the side. The plate at this point was 13 8-10inches thick. The shell penetrated seven inches and then broke up. The metal around the point of impact was slightly dished, but otherwise the plate showed no signs of damage.
The contest for supremacy between armor and shell is always in progress. The Carnegie Steel Company has just completed a plate which it believes will eclipse anything it has yet turned out in point of resistance. The plate is 12 inches in thickness. It is made of nickel steel, but contains a higher percentage of the former metal than has yet been used in the manufacture of service armor, and has been treated by the Harvey process with such changes in the treatment as the new conditions require. A plate of this kind was made about a year ago and was tested. While it broke into three pieces when a shell, given a velocity of 2000 feet per second, struck it, it demonstrated good resistive qualities, and the Carnegie Company determined to manufacture another plate which should be equally resistive but tougher. The firm believes that it has obtained this combination in the plate just finished. In the proposed test a 12-inch gun will be used and the velocity will be about 2000 feet per second, and higher if the results of the first shot demonstrate that another can be successfully fired.—Army and Navy Journal.
A test to-day, March 29, of a port plate at the Indian Head proving grounds indicated that there must be a change in the shape of plates of this character, otherwise their use may become a source of serious danger to vessels in time of war.
A Carpenter projectile, six inches in caliber, was fired at the wing of the re-entrant portion of the plate. The angle of impact was forty-five degrees. The wing was broken off through the point of impact and hurled backward with great velocity, being found about eighty feet in the rear of the target. Had the plate been fitted to the side of a vessel, the fragment, weighing about one thousand pounds, would have been driven clear across the ship and would undoubtedly have caused considerable damage.
The plate tested was five and one-half inches in thickness and was manufactured by the Carnegie Company. It represented a group designed for the battle-ships Kearsarge and Kentucky. It was fitted to a backing of three inches of oak planking and two ½-inch skin plates. A 3-inch plate, to represent a gun shield, was placed alongside the wing of the port plate. The shell was smashed into a myriad of fragments and spattered the experimental shield plate, none, however, getting through. In this latter sense the trial was satisfactory.
The test of the port plate was preceded by a trial of two plates representing the protective deck plates for the Kearsarge and Kentucky. The plates were two and three-quarters inches thick and were fired at with a 6-inch gun. The line of fire made an angle of seven degrees with the surface of the plates—the probable angle at which the protective deck could be struck. The first shell fired—a Carpenter projectile—was broken into fragments. The plate was dished, but was neither penetrated nor cracked.—New York Herald.
England.
The Admiralty and Horse Guards Gazette reports that the trials of the new armor plate intended for the Canopus have yielded some remarkable results. It was of Harveyized nickel steel, 6 inches in thickness, and after four Holtzer projectiles of forged steel, 6 inches in diameter, weighing 100 pounds each, and striking the plate with an energy of 2665 tons, had been discharged against it, the plate was still unperforated. The Gazette says: “On the face of it, this is a good performance, but it is asserted that in the United States, some months ago, a 6-inch Johnson shot, with a soft steel cap, dealt very roughly with a 10-inch plate of similar quality to that now under consideration. According to the same account, an 8-inch Holtzer shot broke into pieces when fired against this marvelous plate. If, too, we are content to rely upon the fact that we must accept accounts from the other side of the Atlantic with many grains of salt, it may be as well to remember that the Russians have made experiments which tend in the same direction. Our own trials of the soft steel cap have not been satisfactory, but other powers appear to have overcome the difficulties with which we have met. Krupp, indeed, has an astonishing record, if all the surrounding circumstances are honestly told.”
At Shoeburyness, on February 28th last, a remarkable result was achieved by a Firth steel projectile fired from the 12-in. wire gun, with a striking velocity of 2300 foot seconds, at a target consisting of an 8-in. compound plate, supported by 6-in. wrought iron plate on 8 feet of oak backing with 3 inches of iron behind it. The striking energy of this shot is 31,160 foot tons, and its perforation on Tresider’s system is 35.05 inches of iron. The front armor, on the regular system of calculation, is equivalent to about 28 inches of wrought iron. The projectile passed not only through this and also the backing and 3-in. skin, if it may be so called, but also passed on, entering a bank of clay and sand 30 yards in rear of the target to such a depth that it has not even yet been recovered.
The target was, of course, overmatched, supposing the projectile capable of performing the task imposed on it, but it may be seen that a projectile which will thus stand up and deliver the great energy embodied in it must be a very execellent one; and its recovery, for which we have hitherto waited, is desirable, in order to see its condition, which we should expect to be very good. We consider thick compound armor plates liable to uncertainty in their quality, but we are informed that this one appeared to be a good sample, and that the officials had no fault to find with it, and were highly pleased with the success of the shot, which the makers understood them to pronounce superior to any hitherto fired. This result is specially welcome, because high-class armor-piercing projectiles are very difficult to make, and greatly needed at the present time.
Russia.
It is reported that in last November a remarkable trial of armor took place at Ochta, near St. Petersburg. An 8-in. gun, 45 calibers long, is said to have driven a shot through a Krupp 10-in. steel plate with a hardened face. The striking velocity is given as 2850 foot seconds, and it is stated that the projectile emerged at the back with a velocity of 700 foot seconds. This is in all respects a valuable experiment. The very high velocity, the hard-faced plate, and the register of the shot after perforation are the very elements to be desired. The projectile must have been an admirable one if it held together intact. We do not know its weight. Russian 8-in. armor-piercing projectiles exist weighing 192.3 lbs., and also 172 lbs. Both are light for this caliber; the British 8-in. shot weighs 210 lbs. This makes the velocity more easy of achievement. Nevertheless it is very high for plate firing. With the heavier shot, the striking energy and perforation through iron would be 10,820 foot tons and 27.3-in., and with the lighter 9685 foot tons and 26.7-in. The shot emerged with an energy, on the supposition of the heavier weight of shot, of 653 foot tons, and of the lighter, of 584 foot tons. From this it follows that either 10,167, or else 9101 foot tons energy was expended in perforating the plate. The projectile in this case exerted a power of perforation equal to 27.0 inches, or 25.5 inches of iron. This means that the figure of the Krupp 10-in. plate was 2.7 inches or 2.55 inches; that is, it represented a thickness of wrought iron bearing this proportion to it in thickness, which argues a very excellent plate. Altogether we could wish that we had more complete data connected with this trial. We need scarcely add that on service such a plate might be safely depended on to defeat the gun. A projectile quickly loses some of its velocity, and so close a range, so direct a blow, and so excellent a shot would form a combination of favorable circumstances that would hardly occur on service.—Engineer.
SHIPS OF WAR.
General.
The war-ships, exclusive of torpedo-boats, launched during the year 1896 for the various navies, and their tonnage, I. H. P., and estimated speed were as follows:
Great Britain.—First-class battle-ships: Mars, Caesar, Illustrious, and Hannibal, all of 14,900 tons, 12,000 I. H. P., and 17 knots speed. First- class cruiser: Diadem, 11,000 tons, 20,000 I. H. P., and 20 knots speed. Second-class cruisers: Arrogant, Furious, and Gladiator, of 5750 tons, 10,000 I. H. P., 19 knots speed; Dido, Doris, and Isis, of 5600 tons, 9600 I. H. P., and 19.5 knots speed. Third-class cruisers: Pelorus and Pactolus, of 2135 tons, 7000 I. H. P., and 20 knots speed. Torpedo-boat destroyers: Avon, Bat, Brazen, Chamois, Crane, Desperate, Earnest, Electra, Vulture, and Whiting, of 300 tons, 6000 I. H. P., and 30 knots speed.
Argentine Republic.—Torpedo-boat destroyers: Santa Fe, Corrientes, Missiones, and Entre Rios, of 250 tons, 4000 I. H. P., and 30 knots speed.
Austria-Hungary.—Coast-defense battle-ship: Buda-Pest, of 5550 tons, 8500 I. H. P., and 17 knots speed.
Brazil.—Second-class cruiser: Barrozo, of 3500 tons, 7500 I. H. P., and 20 knots speed. Torpedo-cruisers: Caramuru and Tupy, both of 1030 tons, 6000 I. H. P., and 23 knots speed.
Chili.—First-class armored cruiser: Esmeralda, of 7000 tons, 18,000 I. H. P., and 23 knots speed. Second-class cruiser: Ministero Zenteno, of 3450 tons, 7000 I. H. P., and 20 knots speed. First-class torpedo-gunboat: Almirante Simpson, of 800 tons, 4500 I. H. P., and 21 knots speed. Torpedo-boat destroyers: Capitan Munez Gamero, Capitan Orella, Teni- ente Serrano, and Guardia Marina Riqueime, of 300 tons, 6000 I. H. P., and 30 knots speed.
Denmark.—Coast-defense monitor: Skjold, of 2160 tons, 2200 I. H. P., and 13 knots speed.
France.—First-class battle-ships: Amiral Bouvet, of 12,200 tons, 14,000 I. H. P., and 17 knots speed; Saint Louis and Gaulois, 11,275 tons, 14,500 I. H. P., and 18 knots speed. First-class cruiser: D’Entrecasteaux, of 8114 tons, 13,500 I. H. P., and 19 knots speed. Second-class cruisers: Catinat, Cassard, and D’Assas, of 3952 tons, 9000 I. H. P., and 20 knots speed.
Germany.—First-class battle-ship: Kaiser Friedrich III., of 11,000 tons, 13,000 I. H. P., and 18 knots speed.
Italy.—First-class armored cruiser: Carlo Alberto, of 6500 tons, 13,000 I. H. P., and 20 knots speed.
Japan.—First-class battle-ships: Fuji-Yama and Yashima, of 12,600 tons, 13,690 I. H. P., and 18 knots speed.
The Netherlands.—Second-class cruisers: Friesland and Holland, 3900 tons, 9250 I. H. P., and 20 knots speed. Station gunboat: Mataram, of 810 tons, 1100 I. H. P., and 13 knots speed.
Norway.—Torpedo-gunboat: Valkyrien, of 380 tons, 3300 I. H. P., and 26 knots speed.
Portugal.—Third-class cruiser: Adamastor, of 1750 tons, 3000 I. H. P., and 18 knots speed.
Russia.—Second-class battle-ship: Rotislav, of 8800 tons, 8500 I. H. P., and 16 knots speed. Coast-defense battle-ship: Admiral General Apraxine, of 4126 tons, 5000 I. H. P., and 16 knots speed. First-class armored cruiser: Rossia, of 12,200 tons, 17,000 I. H. P., and 19 knots speed. Second-class cruiser: Svetlana, 3711 tons, 8500 I. H. P., and 20 knots speed. First-class gunboat: Giljak, of 960 tons, 1000 I. H. P., and 12 knots speed.
Spain.—First-class armored cruisers: Princesa de Asturias, of 7000 tons, 15,000 I. H. P., and 20 knots speed; Christobal Colon, of 6840 tons, 14,000 I. H. P., and 20 knots speed. First-class gun vessel: Dona Maria de Molina, of 823 tons, 4600 I. H. P., and 19 knots speed. Torpedo-boat destroyers: Furor and Terror, of 400 tons, 6000 I. H. P., and 30 knots speed.
Sweden.—Coast-defense battle-ship: Oden, of 3300 tons, 3700 I. H. P., and 16 knots speed.
United States.—First-class battle-ship: Iowa, of 11,410 tons, 10,000 I. H. P., and 16 knots speed. First-class gunboats: Helena, Vicksburg, and Newport, of 1392 tons, 1600 I. H. P., and 13 knots speed.—Journal Royal United Service Institution.
[United States.]
Torpedo Boat No. 5.
Torpedo-boat No. 5, the third and last of the torpedo-boats under construction for the Navy by the Columbian Iron Works, of Baltimore, was launched at the company’s yard, January 6th. Her total cost will be $97,500. She is constructed of steel of the regular Navy requirements, is 160 feet long and 16 feet broad, with a displacement of 142 tons. Her armament will consist of three 18-inch Whitehead torpedo tubes on her upper deck, trained to fire at any angle, and three 1-pounder rapid-fire guns. She is estimated to be capable of a speed of 24½ knots per hour. Her machinery comprises two triple expansion, four cylinder engines, one on each side shaft, in water-tight compartments. The indicated horse-power is 2000. Her coal capacity will be forty-four tons. Her crew will consist of twenty-four men, with four officers.
Torpedo Boat No. 6.
Torpedo-boat No. 6 on its trial trip maintained an average speed of 28.74 knots per hour for a distance of 60 miles. This is equal to 33.1 statute miles per hour, a speed which not a great many years ago would have been equal to the average all-day speed of our passenger trains.
The course was 12 miles long and it was covered in five successive runs. On the first run she crossed the line carrying a steam pressure at the engines of close upon 220 lbs. to the square inch, and her engines were running at the high speed of 405 revolutions per minute. There were two excellent features that were immediately apparent to those on board, the first being the absence of any banking up of a heavy bow wave (the commotion which our readers will notice in the cut being merely the surface foam); the second good feature was the absence of that extreme vibration which is usually felt in a torpedo-boat when she is pushed to her full speed. The quiet way in which she cuts through the water will be an invaluable feature during a night attack. It will increase the chances of stealing up to the enemy unobserved, and the silence and smoothness with which her engines run at high speed will also be greatly in her favor. It was remarked by the officials on board that the vibration was not sufficient to interfere with writing legibly in any part of the vessel. Any one who has been aboard one of the 30-knot torpedo-boat destroyers on a trial trip will appreciate what this statement means. It is well known that torpedo-boat service is about the most trying that exists in any navy, and much of its discomfort arises from the perpetual jarring to which the crew are exposed. The vibration is due to the fact that such enormous horse-power is crowded into a little vessel of extremely light construction.
It is a difficult problem to place in a boat only 175 feet long and 17)4 feet wide a set of 4000 twin engines that shall drive the propellers at over 400 revolutions per minute, and do it without shaking the little craft from stem to stern. The lightness of the construction of No. 6 may be judged from the fact that there is not a plate in her hull that is more than a quarter of an inch thick.
The first heat of twelve knots was run off in 24 m. 52 s., at a speed of 28.97 knots. The second was made in 24 m. 57 s., corresponding to 28.85 knots. The third trial resulted in a speed of 28.78 knots, and the fourth showed a speed of 28.87 knots. The average for the 48 knots was, therefore, 28.87 knots. The last run had scarcely commenced when one of the blowers broke down, a mishap which caused a falling off of the steam pressure and brought down the speed to 28.23 knots, which was 0.73 knot above the contract requirement. The average speed of the whole 60 knots was 1¼ knots above the contract speed of 2½ knots.
The manoeuvring powers of the new boat are excellent, the turns at the end of each run being made in a very small circle, and although the helm was “ hard over,” the amount of “ heel ” was insignificant.
She carries three torpedo launching carriages, one forward on the port side, one amidships on the starboard side, and a third at the stem on the center line. She is also armed with three i-pounder rapid-fire guns. The full complement of the little ship is four officers and twenty-four men.
The remarkable success of this little craft will give increasing interest to the trials of the three 30-knot boats which are now building for the Navy, one on the Pacific coast and two on the Atlantic. If they show as great an advance on contract requirements as No. 6 has done, it is possible that the record for torpedo-boat speed may remain for a few months on this side of the water, or until the new 32-knot destroyers for the English Navy shall have had their trials.—Scientific American.
Trial Trip of the Helena.
With a light westerly breeze and scarcely a ripple on the waters of Long Island Sound, the gunboat Helena speeded across a twenty-seven mile course to-day at a rate of 15.81 knots an hour, exceeding the contract speed of thirteen knots, required of the vessel, to such an extent that she earned a bonus of about $56,000, or $16,000 more than her sister ship, the Wilmington, which had her official trial last Saturday.
Both the Trial Board and the builders’ representatives speak in glowing terms of the two gunboats, especially of the Helena, which steamed over the course and back to-day with machinery working to perfection, and vibration that was scarcely perceptible from her deck.
The boat weighed anchor at half-past six o’clock this morning, and with a parting wish for good luck from the crew of the Wilmington, close by in the stream, glided out of the harbor and was ready for the signal to fly past the torpedo-boat Porter, two hours later, at the starting point of the course. In the fireroom everything was ready for the forced draught, doors were closed air-tight and water-tight, and the blower was revolving at a rate of speed that sucked in the outer air in great volumes.
The ship met the first of the ebb tide at the start and had it against her all the way. But it was not strong, and on the run home she had its favoring impulse. The men in the fireroom were sweltering during the running of the boat under forced draught, but they endured it bravely. They were liberally furnished with ginger ale.
The way the ship sped along on the first reach from the Porter, about three and a half miles from Horton’s Point, made it evident that she was making fast time. On the outward run to Old Field Point the maximum revolutions of the screw were 282 and the minimum 276, the average being 279. The average in knots was 15.34. The run back was made as soon as the ship had made a turn or two and run long enough to permit the indicator cards to be run out.
The total elapsed time for the first half was I hour 45 minutes 37 seconds and for the last half 1 hour 39 minutes and 25 seconds, making the total elapsed time for the full run of twenty-seven knots 3 hours 25 minutes and 2 seconds.
When the run was ended the Helena kept going until she had run out her four hours and made several circles. The coal consumption on her four hours’ run was seven tons.
The Wilmington sailed for Newport News about five o’clock this afternoon, and the Helena will follow to-morrow.—New York Herald.
[England.]
The Isis.
Her Majesty’s second-class cruiser Isis has undergone a very satisfactory thirty hours’ coal-consumption trial at both natural and forced draughts. According to the Naval and Military Record, with natural draught, her engines indicated 8208 horse-power, with a mean speed of 19.8 knots per hour; while at her forced-draught trial her engines averaged 9840 horse-power, with a speed of 21.1 knots per hour. The specifications provided for 8000 horse-power with natural, and 9600 with forced draught. She has been built by the London and Glasgow Shipbuilding Company.
The Niobe.
H. M. S. Niobe was successfully launched on February 20 from the yard of the Naval Construction and Armament Co., Barrow-in-Furness. The vessel is one of eight; six of which are being built by contract, four on the Clyde and two at Barrow, while the other two are being constructed at Pembroke Dockyard. The Niobe is 435 ft. in length between perpendiculars, but the overhanging stern and the projecting ram make the length over all 463 ft. The breadth over sheathing is 69 ft., and her moulded depth to the upper deck 39 ft. 9 in. The mean load draught of the vessel is 25 ft. 3 in., at which draught the displacement is 11,070 tons. The hull of the vessel is constructed of Siemens-Martin steel, with a 4-in. sheathing of wood to 9 ft. above the load water-line, the heavy external framing of the ends, stem and stempost and propeller brackets, and the rudder frame being, as is usual in sheathed vessels, phosphor-bronze castings. The rudder is of the balanced type, and the stem curved outwards under the water so as to form a formidable ram. Two long bilge keels 3 ft. deep are also fitted to prevent rolling. Amidships the vessel’s bottom is constructed on the cellular principle, the inner skin being carried to the protective deck. The double bottom, or the space between the two skins, is minutely subdivided into water-tight compartments which are partly used for the carrying of water, and afford security against sinking should the outer skin be pierced. By water-tight bulkheads and watertight flats the vessel is throughout closely subdivided.
The protection consists of an armored deck of steel plating 4 in. thick at the crown, and extends the whole length of the vessel. It is arched in section, rising from 6 ft. under the water-line at the side of the vessel to 4 ft. above the water-line at the crown of the arch. Under the deck, which is raised for the purpose in way of the engines, are placed the propelling machinery, the steering engines and gear, the capstan engines, the air-compressing machinery, and all the magazines, shell-rooms and torpedo-rooms. The coal bunkers, which have a capacity for over 2000 tons of coal, are arranged along the sides of the boiler-rooms and along the sides of the vessel on the protective deck above the engines and boilers, thus affording most satisfactory coal protection to the machinery of the vessel. The armament of the vessel, as will be seen from the following, is of a most powerful description. There are sixteen 6-in. quick-firing guns, twelve 12-pounder quick-firing guns, three 3-pounder quick-firing guns, two 12-pounder boat and field guns, and eight .45-in. Maxim machine guns. The Niobe is supplied with three torpedo-tubes, one of them firing right aft above the water-line, while two broadside under-water tubes are placed under the protective deck in a special compartment forward. The 6-in. guns and 12-pounder guns will be supplied with ammunition through armored tubes extending from the protective deck to the deck on which the guns are worked. An ammunition passage is arranged on each side of the ship below the protective deck and extending for the whole length of machinery space. The passage is completely protected by coal on top, sides and bottom, so that the ammunition need never be exposed to fire in its course from the magazines to the guns. The total complement of the vessel, including the admiral’s staff, will be 718 men, for whose comfort every provision is made.
The Jupiter.
H. M. battle-ship Jupiter, built by the Clydebank Engineering and Shipbuilding Company, Limited, completed her official trials at Chatham on March 5. On the 2nd the vessel went out for her four hours’ full-power forced-draught trial, during which time a steam pressure of 150 lbs. was easily maintained with an air pressure of .62 in. of water. The vacuum in condensers was 26.6 in. The port engine ran at 101.7 revolutions per minute and developed 6127 indicated horse-power. The starboard engine, running at 102.4 revolutions per minute, developed 6348 indicated horsepower, the collective indicated horse-power being 12,475, which gave a mean speed for the four hours of 18.4 knots. The designed power was 12,000 indicated horse-power, and the speed 17½ knots.
On the following day the eight hours’ natural draught trial was commenced, and this trial was also satisfactory, as with .2 in. air pressure a mean steam pressure of 148 lbs. was kept up, and the engines developed a collective indicated horse-power of 10,248. The mean speed on this trial was 15.8 knots; but record was only taken by log, which is often far from reliable.
On the next day, the 4th, the vessel started the 30 hours’ coal consumption; on this trial, with a mean collective indicated horse-power of 6193, the coal consumed per indicated horse-power per hour amounted to 1.51 lbs. The mean steam pressure during this trial was 146 lbs., the vacuum 26.6 in. The starboard engine, running at 81.5 revolutions, developed 3116 indicated horse-power, and the port engine, running at 81.1 revolutions, developed 3077 indicated horse-power. The Jupiter is of the Majestic type.
The Pegasus.
The Palmers Shipbuilding Company, Newcastle-on-Tyne, launched, on March 4, two vessels, one a third-class cruiser named Pegasus, and one of several 30-knot destroyers, the Flying Fish. The Pegasus belongs to the Pelorus class.
The principal dimensions are as follows: Length between perpendiculars, 300 ft.; breadth, extreme, 36 ft. 6 in.; depth, moulded, 21 ft. 2 in.; displacement, on a mean draught of 13 ft. 6 in., 2135 tons; indicated horsepower, 7000; speed, 20 knots.
The armament consists of eight 4-in. quick-firing guns, eight 3-pounder quick-firing guns, three .45-in. Maxim guns, and two 14-in. torpedo-tubes. Two of the 4-in. guns are placed on the forecastle deck, one on the port side, and one on the starboard side; two on the poop deck, one on each side; and four on the upper deck between the poop and the forecastle, two on each broadside.
Two of the 3-pounders are placed forward on the upper deck, one on each side of the bow; two are placed aft on the upper deck, one on each side of the stem; and four on the upper deck between the poop and forecastle, two on each broadside.
Two of the .45-in. Maxim guns are placed on the hammock berthing amidships, and one on the forecastle deck. The torpedo-tubes are on the upper deck, one on each broadside.
The Flying Fish.
The Flying Fish is the sixth of eight vessels of the same type which Palmers’ Company are building for Her Majesty’s Government. Her dimensions are: Length, 215 ft.; breadth, 20 ft. 9 in., and the displacement is about 300 tons. Her armament consists of one 12-pounder quick-firing gun forward on the conning tower, two 6-pounder quick-firing guns on each side, and one 6-pounder on a platform aft. There are also two revolving torpedo-tubes on deck arranged to fire on either side. The builders have guaranteed a speed of 30 knots, and as a matter of fact the sister ship Star maintained a speed of 31 knots for three hours, proving herself the fastest vessel afloat; the machinery, which has been designed by the builders, consists of two sets of triple-expansion engines, steam being supplied by four of Reed’s water-tube boilers. The Whiting, another of the destroyers built by Palmers’ Company, has run a number of times over the measured mile at an average speed of 30.2 knots, and was kept running for three hours at an average speed of 30.1 knots.
It has been decided to arm the new second-class cruisers Hermes, Highflyer, and Hyacinth, which are now being built, with more powerful guns than was intended when the vessels were originally designed. It was at first arranged that they should have five 6-in., six 4.7-in., and 16 smaller quick-firing guns. Under the new order they will each have eleven 6-in., nine 12-pounders, and six 3-pounder quick-firing guns.
[France.]
Changes in Dockyard Organization.
During the discussion on the naval estimates in the Chamber, Vice- Admiral Besnard, Minister of Marine, announced that it had been decided to effect important changes in dockyard organization, which would comprise the complete separation of the supervision of ships already constructed from those building.
The new regulations have now been settled, but before putting them into practice they will be finally submitted to the Committee of Inspectors- General.
The Temps gives the following account of the new proposals:
The main principle is to be continuity of command of the ship from the day she leaves the hands of the constructor, the naval officer then appointed to the command retaining the same ship till promoted or retired. It will be his duty to be responsible for the armament, mobilization and repairs of the ship, and he alone will be the judge of any alterations to be introduced, as the ship will never afterwards be placed in the hands of the Constructive Department.
The new duties of the naval officer will necessitate the creation of a new department in the dockyards, that of “Direction de la flotte,” at the head of which in each port will be placed a rear-admiral as inspector-general.
The “Service de la flotte” will have its own storehouses and will be in a position to maintain all the ships in its charge in an effective condition. The Constructive Department will only intervene when the repairs are such as to necessitate the assistance of the full dockyard staff; in such a case the “ Service de la flotte” will act towards the Constructive Department in the same way as if the work was being performed by private contract; it will superintend and have entire control of the work performed, and all materials supplied and any changes required in the working hours of the workmen employed will have to receive its sanction, so that it will not be possible in the future to charge other expenses to the repairs of ships with a view of hiding mistakes made in estimates for new constructions—a practice which has often been complained of and condemned by members of the Chamber.
The “Service de la flotte ” will be charged with the duty of preparing ships for mobilization, and for this purpose will possess special storehouses to contain all consumable stores to be issued to the ships on commissioning, and also all non-consumable stores belonging to completed ships. In principle, each ship belonging to a port will have its own separate store, but it may be found possible to avoid this expense and make each ship its own storehouse.
[Germany.]
Restrictions in Use of Wood for Interior Fittings of Ships.
As the result of the experiences drawn from the battle of the Yalu, the use of wood has been much restricted in the new German ships. According to Herr A. Dietrich, Constructor-in-Chief of the Imperial Navy:
“In the outfit and construction of the new German ships wood is used only for a few minor points. Wooden deck planks are no longer laid; steel deck plating is covered with linoleum, sometimes over a layer of cork. In the crews’ quarters the sides of the ships are not ceiled; in the officers’ rooms the ceiling is made of steel plates 1½ millimetres thick and lined with cork. For cabin bulkheads the steel is covered with thin woollen cloth, and with cork lining underneath where it is desirable to exclude sound or lower the temperature. Where heat is radiated from engine or funnel casings, cork lining is resorted to. All wood is removed from the ammunition rooms, save the racks for shells and powder charges, which are still made of wood. For all ladders and steps steel is used. The handrails on the conning bridges are no longer of wood, but of some other material which will not burn or splinter, and which is more agreeable to the touch of the hand than steel or brass. Chart-houses and captains’ rooms on bridges are entirely made of steel and fitted out with non-combustible materials. Since all such changes will be a little exaggerated, it seemed to be advisable to abandon wood for the interior fittings, and especially for the furniture, and to resort to fireproof material which will not splinter. Many things were tried; furniture was made of steel and aluminum, lined with cork and covered with linoleum or canvas; but it was not equal to wood furniture. Only the bedsteads are constructed of iron, steel or brass. The insignificant quantity of wood in the few pieces of furniture when ignited is not a dangerous source of smoke, but rather it is the outfit of the state-rooms, the mattresses, blankets, clothing, books, etc. However, for the present, wood cannot be abandoned entirely. Top signal masts, flag poles, etc., will be made of steel, but there one cannot save weight. The fighting capacity of the ships is without doubt increased through these innovations, since the ship is less apt to burn, the effects of splinters are restricted, and considerable weight is saved, which is available for ordnance and armor.”
It may also be mentioned that in German ships-of-war the protective under-water deck is never cut through either for ventilation or coaling purposes.
[Spain.]
Torpedo-boat Destroyers Furor and Terror.
The torpedo-boat destroyers Furor and Terror, designed and built by Messrs. James and George Thomson, Limited, Clydebank, to the order of the Spanish Government, have now completed their trials, and have arrived in Spain. Although similar in general design to the destroyers of the British Navy, there are several departures in detail, and the vessels are in some respects more nearly akin to the torpedo gunboats. For example, they are fitted with teak upper decks in addition to a complete steel deck; double awnings for the whole length of the vessel, with side curtains hanging to the water’s edge, electric lighting throughout, and a number of electrical ventilating fans for insuring a supply of fresh air to the officers’ and crew’s quarters; so that the vessels will be much more habitable than an ordinary torpedo-boat destroyer when serving in the tropical or semi-tropical climates for which they are intended. The contract provided that the mean speed should be determined by four runs on the measured mile, and by a further trial of two hours’ duration, during which the speed should not be less than 28 knots. It was further stipulated that a load of 75 tons should be carried on trials, which is more than twice the load required in the case of vessels of a similar type built for the British Navy.
The vessels have a length of 220 ft., breadth 22 ft., and have a moulded depth of 13 ft The loaded displacement is 380 tons. The armament consists of two 14-pounder quick-firing guns, the one mounted forward on top of the conning tower and the other aft; two 6-pounder guns of the same type mounted on the broadside, and two 37-millimetre automatic quick-firing guns, one on the starboard and the other on the port bow. AH these guns have been supplied by the Maxim-Nordenfeldt Guns and Ammunition Company, Limited, and are of the latest and most improved pattern. The vessels are also equipped with two torpedo-tubes, 14 in. in diameter, mounted on the upper deck, so as to fire off either side of the ship. The torpedo-tubes are on the Schwartzkopff system. Four torpedoes are carried, and there is, of course, a complete installation of aircompressing machinery for charging them, the engines and pumps being in the engine-room.
After some preliminary trials, the Furor successfully passed her official forced-draught trial on October 30. The mean speed of four runs on the measured mile exceeded the contract by about a quarter of a knot, and the revolutions were maintained without difficulty for the two hours’ trial. The Terror, after a single preliminary trial, completed her natural-draught trial, and, at the next succeeding trial, successfully completed her official forced-draught trial. The natural-draught trials were of the same duration as the forced-draught trials, and it was provided by the contract that a speed of 21½ knots be maintained with the air pressure in the stokeholds not exceeding ¾ in. of water. It was found that this speed could be maintained with very great ease; indeed, the stipulated speed was exceeded by about a knot
After the speed trials, the firing trials of the guns were carried out to the entire satisfaction of the inspecting officers. The terribly destructive nature of the fire, especially from the automatic guns, was very apparent, a perfect hail of projectiles of 37 millimetres, or about i'/j in. in diameter, being delivered by these guns, and continued so long as the person firing the gun kept his finger pressed on the trigger, the whole of the operations of loading and firing being automatically performed by the energy of the recoil.
On Saturday, February 6, the Clydebank Engineering and Shipbuilding Company (Limited), launched from their yard at Clydebank a twin-screw torpedo-boat destroyer built to the order of the Spanish Government. The vessel, which was named the Audaz, is of greater tonnage than the Furor and Terror, lately delivered from the same yard, and will carry the same armament, but she will be two knots faster.
The firm of J. and G. Thomson, Clydebank, has received contracts from the Spanish Government for the construction of sixteen torpedo-boat destroyers of the Furor and Terror type.
New Spanish Floating Dock.
The well-known shipbuilders on the Tyne, Messrs. Robert Stephenson & Company, Limited, have definitely concluded negotiations with the Spanish Government for the building of a floating dock, to be located at the port of Olongapo, Philippine Islands. The dock, which will be the largest yet constructed anywhere, is of the following dimensions: Length, 450 ft.; width, over pontoons, 117 ft.; depth to the top of side walls or girders, 38 ft. 6 in. The dock, when completed, will rest on a series of six pontoons, each of which will be between 13 ft. and 14 ft. deep. These latter will be constructed of iron; while the side girders, which constitute the walls of the dock, will be of steel. The arrangement of the pontoons in the design is such that in the event of any of them getting damaged and requiring to be repaired, it can be temporarily detached from the rest of the structure and floated on to the dock itself. The dock is intended to lift vessels up to 12,000 tons, and will have an equipment of four powerful pumping engines, capable of pumping 12,000 tons of water in two hours. Though capable of taking vessels 500 ft. long, the weight of which will be pretty evenly distributed over the whole of the structure, it is specially designed to lift vessels of the maximum weight—12,000 tons—the length of which may not exceed 300 ft. In the latter case it is evident the pressure will be concentrated in a smaller area, and will, therefore, test more severely the stability of the whole. To give to the structure the necessary strength for resisting central pressure or distributed pressure with equal certainty, special care has had to be taken in the designing. For convenience of shipment the dock is to be built in sections, which in due course will be sent out to Olongapo, where the structure will be finally put together and completed.—London Engineer.
[Portugal.]
New Cruisers.
The Portuguese Government has placed contracts with La Société des Forges et Chantiers de la Méditerranée for two cruisers of 1800 tons displacement, to be built in Havre. Dimensions to be as follows: Length, 246 feet; beam, 33 feet; draught, 14 feet; horse-power, 2650. The armament comprises two 15-cm., four 12-cm., and eight 4.7-cm. Canet guns, all on Canet mounts with shields. The torpedo armament consists of a submerged bow tube. Speed to be 15 knots.
[Norway.]
Harald Haarfagre.
On January 4 was launched from the Elswick yard on the Tyne the Harald Haarfagre, a new armor-clad for this government. She is the first important armored ship built for the Norwegian Navy, and her dimensions are as follows: Length, 280 feet; beam, 48 feet 6 inches; and with a mean draught of 16 feet 6 inches, her displac.ment will be 3500 tons. Protection is afforded by an 8-inch armor water-line belt and a 2-inch armored deck. The armament will consist of two 21-cm. (8-in.) guns, mounted in hooded turrets protected by 8-in. armor, one forward and one aft, four 6-in., six 12-pounder, and six 1½ -pounder guns, all Q. F., with two discharges for 18-in. torpedoes. A sister ship is also under construction at the same yard.
Valkyrien.
The torpedo-boat destroyer Valkyrien, completed last year by the Schichau firm at Elbing for the Government, maintained a mean speed of 23.2 knots during her official trials, the engines making 240 revolutions and developing 3300 I. H. P., the boilers being Thornycrofts. She is a vessel 188 feet 6 inches long, 23 feet beam, and with a draught of 7 feet has a displacement of 380 tons. The armament consists of two tubes on deck for 18-inch torpedoes, one amidships and one aft, with one 6-pounder and one i-pounder Q. F. guns. The cost of the Valkyrien was defrayed by subscriptions collected by the Patriotic Ladies’ League.
Delfin, Hai, and Hval.
Three first-class torpedo-boats, the Delfin, Hai, and Hval, have just been completed and delivered by the Schichau firm of Elbing; they are 120 feet long, are fitted with Thomycroft’s boilers, and have a mean speed of 23 knots. They carry two 18-inch torpedo-tubes on deck and two i-pounder Q. F. guns.
[Sweden.]
Oden.
The Oden, one of the new type of improved Svea battle-ships, is now almost ready for her trials, while two others, the Thor and Njord, are nearly ready for launching. The Thor is being constructed at the yard of the Bergsunds Maschinenfabrik in Stockholm, and the Njord at the yard of the Lindholmens Fabrik in Gothenburg; the engines are being constructed by the Motala firm; both ships are to be completed by the end of 1898. The dimensions of these ships are as follows: Length, 277 feet 4 inches; beam, 47 feet 10 inches; and with a maximum draught of 16 feet 6 inches they will have a displacement of 3400 tons. The engines are to develop 3700 I. H. P., giving a speed of 16 knots. There is a 12-inch armor water-line belt for about two-thirds of the length of the ship, and a 4-inch casemate amidships for six 15-cm. (5.9-inch) Q. F. guns; the principal armament consists of two 24-cm. (9.4-inch) guns, one forward and one aft in hooded barbettes protected by 12-inch armor, and there are also ten 6-pounder Q. F. guns, four machine guns, and an underwater bow torpedo-tube. The armor for all three ships is being made by the French firm of Schneider at Creusot. The heavy guns for the Oden and Thor will be made by the French firm of Canet, while those for the Njord will come from the Swedish manufactory at Bofors. It is stated that the Bofors establishment is to be taken over by M. Nobel, of Paris, and will be greatly enlarged.
Jarnan and Edjern.
The two torpedo cruisers Jarnan and Edjern, now nearly ready for launching, are of a similar type to the Omen, their dimensions being as follows: Length, 220 feet; beam, 27 feet 6 inches; a displacement of 670 tons; with engines developing 4000 I. H. P., to give a speed of 19 knots. The armament will consist of two 12-cm. (3.9-inch) Q. F. and four 6- pounder Q. F. guns, with one torpedo-tube.
[Brazil.]
Coast Defense Battle-ships.
The two small coast-defense battle-ships building for this government at the La Seyne Yard, near Toulon, are to be called the Marshal Deodoro and Marshal Ypiranga. Their dimensions are to be as follows: Length, 267 feet 6 inches; beam, 48 feet; displacement, 3162 tons, with a draught of 13 feet 2 inches. Protection will be afforded by a water-line belt of 13.7 inches of nickel steel, tapering, however, to about half that thickness at the bow and stern, and by an armored deck 1.3 inches thick. There will also be a central redoubt protected with 28-inch nickel steel armor, and two armored turrets 8 inches thick, one forward and one aft, for two heavy guns, which will be 24-cm. (9.4-inch) Canet guns; four 12-cm. (4.7-inch) Q. F. guns will be mounted in the redoubt and two 15-cm. (5.9-inch) howitzers on the spar deck, with four 6-pounder, two i-pounder Q. F. guns, two machine guns and two submerged tubes. The engines will develop 3400 I. H. P., steam being supplied by Lagrafel d’Allest water-tube boilers, and the speed is to be 15 knots. The coal storage will be 236 tons, and the crew will consist of 200 officers and men.
The Caramuru.
The new torpedo cruiser Caramuru, one of three building at the Germania yard at Kiel for the government, has lately completed her steam trials, when a mean speed of 22 knots was obtained. The following are the dimensions of the Caramuru and her two sisters: Length, 255 feet 6 inches; beam, 29 feet 6 inches; and with a draught of 9 feet 9 inches they have a displacement of 1030 tons. The engines are to develop 6000 I. H. P., giving a speed of 23 knots. The armament consists of two 4-inch, six 6-pounder, and four 3-pounder guns, all Q. F.’s, with two broadside and one bow tube for 18-inch torpedoes. Two first-class torpedo-boats are building at Elbing, and two river monitors at Rio de Janeiro.—Journal of the Royal United Service Institution.
[Chili.]
Esmeralda.
The new first-class cruiser Esmeralda has just been completed by Sir W. G. Armstrong & Co., at Elswick, for the Chilian Government. She may, perhaps, be regarded as a very much improved Blanco Encalada, which was completed in 1894 for the same government. She has a much more powerful armament, greatly increased protection, greater speed, and a larger coal-carrying capacity than the last-named ship; and now that she has satisfactorily passed through all her trials, and is lying ready to start for her destination, she must certainly be regarded as one of the most formidable cruisers afloat. A brief description will convince any one of this who will take the trouble to compare her qualities with those of cruisers of the same and greater displacement belonging to other nations.
Her length between perpendiculars is 436 feet; beam, 53 feet 2 inches; mean draft, 20 feet 3 inches, and a displacement of just over 7000 tons. Her full coal supply is 1350 tons, an amount which would enable her to cross the Atlantic at a speed of over 20 knots and, of course, give her an enormous radius of action at more moderate speeds. The vessel is sheathed with wood and coppered. Her armament is as follows: Two 8- inch Q. F. guns, placed one forward and one aft; sixteen 6-inch Q. F. guns, four firing right forward and four right aft, and the remaining eight on the broadsides; eight 12-pounder Q. F. guns, ten 6-pounder Q. F., four Maxim guns, and three torpedo-tubes.
In addition to a curved protective deck, V/2 inches to 2 inches in thickness, extending over her whole length and covering all the vitals of the ship, she has over more that three-fourths of her length a belt of Harveyized armor 6 inches thick and 7 feet deep, terminated by armor bulkheads of the same thickness. Her conning tower, containing all apparatus for working and fighting the ship, is protected by Harveyized armor 8 inches thick.
The Esmeralda was commenced during the latter half of 1895, and she has been complete for some weeks, so that she has been considerably less than a year and a half building—a remarkably short time for a vessel of her size and power. Her machinery is of the four cylinder vertical triple-expansion type, driving twin screws; and the I. H. P., which was exceeded on trial, is 15,000 with natural draught. She is provided with forced draught, which would give her a power of 18,000 horses, but the Chilian Commission has been so satisfied with the results of speed and power attained with natural draught that no use has been made of forced draught.
Her official steam trials took place in September, and consisted of a full-speed trial with natural draught, which lasted for six consecutive hours. During the trial runs were taken on the measured mile, and a mean speed of over 23 knots was obtained with and against the tide, and the H. P. which gave this speed was maintained and part of the time exceeded during the six hours. In addition to the above, an endurance trial was taken lasting 24 hours, during which three-fifths of the full power, namely, 10,800 horses, was maintained, giving the vessel a speed of over 20 knots per hour.
The gun-firing trials took place off the Tyne on February 16th, the guns and structure of the ship being put to the severest possible tests. The 8-inch gun and four 6-inch guns were fired simultaneously in the line of the keel and horizontally, the shot passing only a few feet above the deck over the admiral’s state-room, and yet no damage was done. All the guns were also fired simultaneously by electricity, which is also used as the motive power for training the 8-inch guns and the hoists for the 8-inch and 6-inch ammunition.—Journal Royal United Service Institution.
The official trial of the torpedo-boat Injeniero Hyatt, built by Messrs. Yarrow & Co. for the Chilian Government, took place at the mouth of the Thames on Monday, February 15th, when a speed of 27.2 knots was obtained over the Maplins with a pressure of steam of 195 lbs. This vessel and the torpedo-boat Cirujano Videla, tried last month, are being fitted out to join the Chilian squadron, which will shortly leave this country.
[Japan.]
Japan’s Navy in 1906 will, according to present plans, consist of 6 line- of-battle ships, 12,517 to 15,140 tons; 1 second-class battle-ship, 7315 tons; 6 first-class armored cruisers, 9000 tons; 7 second-class cruisers of over 4000 tons; 6 third-class cruisers of over 3000 tons, and 12 fourth-class cruisers or gunboats of over 1500 tons.
[China.]
At the Vulcan Shipbuilding yard, Bredow, near Stettin, where the Chinese torpedo gunboat Fei Ying was built in 1895, three protected cruisers for the Chinese Government are in hand. They are sister ships of 2950 tons, 328 ft. long, with 41 ft. beam and 16 ft. 6 in. extreme draught. Protection is given by steel decks varying in thickness between 1½ in. and 2½ in., and the guns are to have steel shields. The armament will consist of three 6-in. and eight 4-in. Krupp quick-firers, six 1.4-in. Hotchkiss quick-firers, and six Maxims, and there will be three above-water torpedo- tubes. The machinery has been built at the Vulcan Works, and engines of 8000 horse-power, driving twin screws, are to give a speed of 19.5 knots. The normal coal supply of each cruiser will be 220 tons, and her complement 250 officers and men. At the same yard the German second-class cruisers K (5650 tons) and N (5900 tons) are in hand.