ANNALEN DER HYDROGRAPHIE.
Part IV., 1885. Sailing Directions for the Gilbert, Marshall and Caroline Islands.
Part V. Theory of the Lamont instrument for observations of the earth’s magnetism. Surveys on the west coast of Patagonia. New passage between the Gulf of Trinidad and Gulf of Penas, with table. Table for correcting the longitude or hour angle for a change of latitude, and other tables.
Part VI. Sailing Directions for SE. and NE. coast of New Guinea and the adjacent waters.
Part VIII. Deep sea researches in the Caribbean Sea by the U. S. Coast Survey. The Falkland Islands.
Part IX. Contribution to the cartography and hydrography of the coast of Upper Guinea between Cameroon and Accra. Sailing Directions for the Java Sea, the Celebes and the Sulu Archipelago.
ENGINEERING NEWS AND AMERICAN CONTRACT JOURNAL.
October 3, 1885. New ordnance material of Europe, by Captain W. H. Bixby, Corps of Engineers, U. S. A.
This periodical will publish by permission of the War Department, during the last quarter of the year 1885, a portion of an official report made by Captain Bixby upon his investigations in Europe in 1881-1882, “upon turrets, armor- plate, and the mounting and manoeuvring of guns of large calibre.”
The following is an abstract of the index of the report to be published:
Heavy guns; wire-wound and ribbon guns.
Non-recoiling gun carriages; Krupp’s non-recoiling muzzle-pivoted gun- casemate gun, with detail, cost, time of manufacture, service, advantages, disadvantages and possible modifications, etc.; Gruson’s non-recoiling minimum embrasure gun-cupola gun; Krupp’s non-recoiling trunnion-pivoted gun.
Gun carriages with slight recoil; Krupp’s slight recoil trunnion-pivoted guns; Albini carriage.
Yoke-mountings for 43-ton gun on ordinary carriage.
Front parapet anchorage.
New muzzle-pivoting mechanisms:—Shaw carriage; Heathorn; King; Krupp; Gruson (old model); Gruson embrasure ring; Armstrong minimum embrasure carriage, Gruson min.-embrasure carriage.
Disappearing-gun gun carriages:—Moncrieff and King counterpoise; Moncrieff hydro-pneumatic; Labrousse; Armstrong; Razkazoff.
Under-cover loading of heavy guns:—English official system; Armstrong system, for small guns, for 100-ton guns.
Manoeuvre of heavy guns:—Bibliography of.
New forms of projectiles:—New Palliser ribbed abd jacketed chilled-iron projectiles; Gruson new chilled-steel projectiles.
New explosives: Gruson’s new explosive of 1881; miner’s powder; ammonia-nitrate powder.
Accuracy of fire of modern ordnance:—Field guns, heavy guns; rifled mortars or howitzers.
New methods of protection against moisture on wood, stone and metal surfaces:—Celluloid lining for ammunition cases; cork paint for exposed ironwork; cork composition for floors of magazines; ventilation of magazines; Cohausen’s psychroscope.
List of Plates to accompany report:
[Table of Plates]
FRANKLIN INSTITUTE JOURNAL.
August, 1885. The theory of the finance of lubrication, by Professor R. H. Thurston.
September. The metallurgy of steel, by Pedro G. Salom. On the jacketing of working cylinders of steam engines, by A. S. Greene, C. E.
The question of the relative merits of jacketed and unjacketed cylinders has often been discussed, but has not yet been disposed of in a satisfactory manner. In discussing the subject Mr. Greene states that since all the heat supplied to the expanding steam from the jacket must first be obtained from the original source, namely the boiler, and the jacket being also subject to a further loss of heat from radiation from the exterior surfaces, it follows necessarily that the amount of effective heat for transmission into work by the medium of the jacket is much less than that drawn from the boilers to supply it. It is in fact a sort of “robbing Peter to pay Paul’’ process, with this disadvantage, that the amount received by Paul is very considerably less than that of which Peter has been robbed. If it be really advantageous to reheat the expanding steam in the working cylinder, it has been suggested that a more rational and effective process be employed, in which the resistance of the cylinder shell to the transmission of heat, and the loss from radiation, from the excess of the surface of the jacket over that of the working cylinder, would be avoided. This could be easily accomplished by supplying a small jet of steam from the main steam-chest or steam-pipe directly to the interior of the working cylinder during expansion, by means of an automatically operated valve; the ports for this purpose would be small and need not be as large as the section of steam pipe used for supplying the jacket, for the same amount of heat applied directly would certainly effect a greater amount of reheating than could possibly be done through the medium of a jacket.
Whether there is any advantage to be derived from the use of the steam jacket or not, there are several disadvantages with which it is inevitably attended. Extra labor and material are required in construction, there is liability to loss of castings from their complicated nature, besides extra weight and space occupied. In Mr. Greene’s opinion the best place to utilize the heat of the steam in producing work is within the working cylinder, preventing as much as possible the losses of heat, with light sheet-iron to enclose a space corresponding to the jacket, to contain air, which enclosure should be tight enough to prevent circulation of air and loss of heat from convection, and then carefully felted and cased with wood. With a cylinder fitted in this manner it is believed better results would be obtained, and certainly many extra pipes, valves, traps, and much annoyance would be avoided.
October. On tidal theory and tidal prediction, by E. A. Gieseler. An account of the experiments made upon a condensing compound engine by a committee of the Industrial Society of Mulhouse, in Alsace, Germany; by Chief Engineer Isherwood, U. S. N.
In 1878, the Industrial Society of Mulhouse offered a medal of honor for the first compound engine built in Alsace that would give a French horse-power for not more than 9 kilogrammes of steam used per hour, equivalent to about 17.44 pounds per English horse-power. In 1879, the challenge was accepted under circumstances which Mr. Isherwood proceeds to describe.
The mean of the experiments with steam expanded 6.25 times gave the consumption of feed-water at the rate of 17.1 pounds per indicated horsepower, and with steam expanded 9.64 times with the same initial pressure, 92 pounds above the atmosphere, the weight of feed-water used was 16.93 pounds, showing no practical gain for the increased rate of expansion.
When the lower rate of expansion—6.25 times—was employed, 24.7 per cent, of steam admitted to the engine was condensed in the high pressure cylinder while the steam port was open. With the larger rate of expansion 43 per cent, was condensed when the cut-off valve closed. The re-evaporization of the water of condensation in the small cylinder under the lessening pressure due to the expanding steam, and at the expense of the heat in the metal of the cylinder and in the water of condensation, reduced the amount of condensation at the end of the stroke to 6.57 per cent, for the smaller measure of expansion, and to 11.67 per cent of the steam admitted, for the larger measure.
At the end of the stroke of the large cylinder, the water in it due to the condensation of steam was 7.29 per cent, of the steam evaporated in the boiler for the smaller measure of expansion, and 10.5 per cent, for the larger measure of expansion. The re-evaporated steam which passed from the small cylinder to the large one during the exhaust stroke of the former was utilized upon the piston of the latter, and by fitting the large cylinder with a lap cut-off valve, this re-evaporated steam was used expansively in that cylinder.
In conclusion, Mr. Isherwood bases the economic superiority of the compound engine over the simple one worked between the same boiler and condenser pressure, with the same measure of expansion and the same reciprocating speed of piston, upon the fact that the steam condensed in the small cylinder by the interaction of its metal is used upon the piston of the large one during its whole stroke, and expansively too if a cut-off be applied there. There is, perhaps, a necessity for stating that condensation by the interaction of the metal is a totally different thing from the condensation in the cylinder of a portion of the steam to furnish the heat transmuted into the power developed by the expanding steam after the cut-off closes. In the engine experimented upon both cylinders were steam-jacketed.
INSTITUTION OF MECHANICAL ENGINEERS, LONDON.
April, 1885. The Maxim automatic machine gun.
Much has been heard in various professional periodicals in regard to the merits of the above gun, and descriptions have also been given more or less complete. But the explanation of the system and its working by the distinguished inventor himself before the Institution of Mechanical Engineers, London, and published in the Proceedings of that Institution for April, 1881;, is by far the clearest and most complete. It may be well to call attention to the fact that if at first sight it may seem to be a complicated piece of machinery, though this is by no means admitted, it must be remembered that the numerous parts are chiefly incidental to a gun using small-arm ammunition and requiring a mechanical feed. The main principle of the gun has been applied by the inventor to a larger calibre—the weight of the shot being about 3 pounds—and which when perfected will do away with a large number of parts which are necessities in the smaller gun, since a gravity feed will be used.
A gun which automatically loads and fires, leaving the operator perfectly free to aim, must suggest itself most favorably to artillerists.
The inventor’s device to direct the smoke away from the muzzle of the piece or to get rid of it altogether seems most ingenious, and will be appreciated by any one who has noticed the firing of machine guns on a calm day or when firing against or with the wind.
JOURNAL DU MATELOT.
No. 27, 1885. The Condor.
This torpedo cruiser, launched at Rochefort last May, was designed by M. Bussy, and may be said to have no counterpart in foreign navies. She is a twin-screw steel vessel, at the same time a torpedo scout of great speed and a counter torpedo boat, armed solely with fish torpedoes and guns of small calibre, 216½ feet long, 29 feet beam, 12 feet 5 inches draught forward and 15 feet 5 inches aft, displacement 1272 tons. A compound engine drives each screw, and with forced draft the speed is expected to exceed 17 knots. The hull is divided into ten water-tight compartments by thwartship bulkheads reaching to the armored deck, while fore and aft bulkheads add to the strength. A steel turtle-back protective deck extends the length of the vessel. There are no masts except for signals and revolving cannons. The armament consists of five torpedo tubes, two forward, one astern, and one on each broadside, 5 steel 10 cm. guns and 6 Hotchkiss revolving cannons.
The Acheron.
A twin-screw steel armored gunboat; was launched at Cherbourg in April last. She is 181 feet long, 40 feet 4 inches beam, with a displacement of 1640 tons. The water line is protected by an armor belt; the armament will be a 27 cm. gun in barbette tower and two 10 cm. guns.
MITTHEILUNGEN A. D. GEBIETE D. SEEWESENS.
Vol. XIII., Nos. 3 & 4. Measurement of the fuel used by marine engines at different rates of speed. Recent additions to foreign fleets.
An interesting resume of the armored and other vessels projected and completed for the navies of the various maritime powers.
Nos. 5 & 6. Side and deck armor. Improvements in distilling apparatus, the Perrog system. Rain clothes for the crew. Electric boats.
No. 7. Innovation in the preparation of gunpowder. Compound engines of the Italian cruiser Etna. The English Navy. The German Navy.
No. 8. The problem of determining the deviation of a steamer’s compasses at sea. Chronograph of the present time. Approximate construction of the stability curve by the use of paper patterns.
The Japanese Navy.
A description of three new cruisers and a sea-going torpedo boat.
NAVAL AND MILITARY GAZETTE.
August 26, 1885.
The Chilian ironclad Blanco Encalada was docked recently for the first time since she left England ten years ago. The iron bottom had then been covered with teak plank with iron fastenings, and sheathed with zinc. Notwithstanding the ten years’ immersion, the bottom was found to be remarkably clean, and the waste of zinc scarcely as much as had been anticipated.
NAUTICAL MAGAZINE.
July, 1885. The Maritime Inventions Exhibition; the curszierger.
An instrument devised by Captain Martinolich, of the Austro-Hungarian Lloyd Steamship Company, to take the place of parallel rulers and chart compass cards in determining course and distance on sea charts. It consists of a rectangular ruler 45 cm. long and 6.8 cm. broad, to which is pivoted at one end another ruler of about the same length; on both are scales of equal parts. At the pivot end are two superposed concentric compass cards of different diameters. The ruler is placed on the nearest meridian, and the movable arm is brought over the points between which course and distance are required. The device is ingenious and useful, but will not take the place of parallel rulers, especially those of the Sigsbee type. The diastimeter is another device of the same inventor. It is a diagram by which problems in coast navigation may be solved practically.
Improved method of attaching rope stoppers to ships’ decks.
By this invention the stopper takes the direct pull of a rope in any direction.
October. Lighthouse illuminants (report of the Trinity House Committee).
“That for ordinary necessities of lighthouse illumination mineral oil is the most suitable and economical illuminant; and that for salient headlands, important landfalls, and places where a powerful light is required, electricity offers the best advantages.”
The action of electricity upon ship’s compasses.
In this communication Commander Chas. S. Hudson sounds a note of warning in regard to connecting one wire of a dynamo with the ship’s frame for the return current, claiming that the magnetic conditions of the hull are changed, and that the compasses are affected thereby. An extract from The Marine Engineer for August, 1881, is given: “A steamer has just arrived in London from the Clyde steered by electricity; it was most successful, but the compasses were so affected by electricity as to be practically useless.”
REVUE MARITIME.
July, 1885. Naval battles in the middle of the 17th century. The late Admiral Courbet. The French armored cruiser Requin.
Launched at Bordeaux June 13; length, 271 feet; beam, 59 feet; draught, 23 feet; displacement, 7210 tons; thickness of armor, 19.7 inches. She has twin screws, and is calculated to make 14.5 knots and to develop 6000 horsepower. The hull is of steel, double bottom, and she is to carry two steel 15½-in. guns in turrets.
The Japanese cruiser Takachiko-kan.
This vessel, similar to the Naniwa-kan, was launched May 16; length, 229½ feet; beam, 34 feet; draught, 16 feet 2½ inches; displacement, 3600 tons. The calculated horse-power is 7500, and the speed expected from 18 to 18½ knots; the two engine and fire-rooms are completely separated. She will carry two 10-in. guns on central pivots, six 6-in. guns in broadside, ten machine and two rapid-firing guns, and four torpedo tubes.
August. Trial of the Brazilian armor-clad Aquidaban.
At full speed, natural draft, the speed was 15.257 knots; forced draft, 15.818 knots; with one screw, 11.447 knots. In the latter case it was found necessary to keep the rudder at an angle of 15°. A coal consumption of 15 tons a day gave a speed of 14 knots, enabling her to steam a little more than 17 days.
September. The canal from the North to the Baltic Sea. Naval construction and men-of-war. The Francesco Morosini.
This Italian steel armor-clad was launched at Venice July 30. Length, 328 feet; beam, 54 feet 9 inches; draught, 25 feet; displacement, 10,045 tons. She has twin screws and a coal capacity of 850 tons, and is expected to develop 10,000 horse-power and 16 knots speed. The armor, manufactured by the Creusot process, varies from 17.7 inches to 14.2 inches in thickness. The armament is four io6-ton guns, two 6-in. guns, machine guns and five torpedo tubes.
October. Observations on the relative speed of wind and ship, taken aboard the Jean Bart. Optical telegraphy. Spanish 15-cm. gun.
This is of cast iron, reinforced by a double steel tube extending 50 cm. beyond the trunnions. The length is 30½ calibres; the weight, cast iron 12,225 lbs., tubes 2676 lbs. During the trials projectiles were used of 3½ calibres length, with one expanding ring. Several plates representing a total armor thickness of 10.2 inches were penetrated. The initial velocity Was 2165 feet; the range at 19° elevation, 8750 yards. This gun was manufactured at Trubia, Spain, and was invented by Don Salvador Diaz Ordonez, of the Spanish Artillery.
KEVUE SCIENTIFIQUE.
July, 1885. Naval art; collisions at sea, means to prevent them at night.
Principally calling attention to the defects of the present system of ship’s sidelights, and suggesting that an international conference assent to and regulate the routes of ships, and especially determine certain rules for those steamers of more than 15 knots speed. There are three remedies between which to make choice, likely to lessen the chances of collision:
I. Routes determined beforehand, and outside of which no vessel in a fog is to steam more than 14 knots. 2. Or a greater number of lights for high-speed steamers. 3. Or better: stronger, more powerful lights, electric lights if necessary, which can be immediately replaced if injured.
The conference should examine all the different methods proposed to give as nearly automatically as possible, the proper manoeuvre to perform in each case. After proper examination and discussion let the conference choose one, or make one from the combination of the better portions of each system. The important point is to recommend the adoption of a uniform system.
Three officers have called attention to this important question—in these days of rapid steam navigation nothing concerning safety at sea is more important— Captain C. E. Buckle, R. N., and Lieutenant Alfred Collet, F. N., principally in regard to better rules and more definite routes, suggested by the great improvements in compasses and sounding machines; and Commander Hoff, U. S. N., advocating the employment of double lights.
RIVISTA DI ARTIGLIERA É GENIO.
August-September, 1885. The effect of bombardment on the materiel and on the personnel.
An interesting resume of bombardments since 1684. The writer arrives at the conclusion that in general, resistance is possible in bombardments of greater or less severity whether sustained in works, intrenchments, or forts, as well as in heavier bombardments, or those against cities partially or entirely exposed to the destructive effects.
Translation of Vol. X., No. 4, of Proc. Nav. Inst., pp. 570 to 593.
RIVISTA MARITTIMA.
June, 1885. The Italian merchant marine.
On December 31, 1884, there were 7072 sailing vessels with a tonnage of 848,704, and 215 steamers with a tonnage of 122,297.
The Italian Navy estimates.
July-August. Electric lighting on board the Giovanni Bausan.
ROYAL ARTILLERY INSTITUTION, PROCEEDINGS.
September, 1885. The attack of armor by artillery, by C. Orde Brown, late Captain R. A.
“For the sake of distinction, armor may be divided into two classes, soft and hard. Under the head of soft armor may be included all shields which admit of perforation, which, when possible, is the best method of attack. Soft armor then includes all kinds, consisting of wrought-iron only, whether laminated, plate-upon-plate, or solid. Occasionally a steel or steel-faced plate has had a hole made completely through it without breaking it up, but this is not generally possible. Wrought-iron was universally employed until chilled iron armor was adopted for certain land forts on the Continent. This was first tried in 1868 with success, and in 1873 it met with very marked approval. After the Spezzia trials of December, 1876, steel and steel-faced armor came gradually into use. Up to that time our experiments in England were almost entirely confined to the problem of the perforation of wrought-iron; and even now perforation is kept in view with steel-faced plates in a measure, for a shot is generally considered to be a match for a steel-faced plate when it is capable of perforating some estimated equivalent thickness of wrought-iron. Suppose, however, that such a relation can be established, its application is limited to the few cases when perforation without much fracture is effected, and may greatly mislead any one who uses it indiscriminately, for the following reason: Power of perforation varies inversely with the diameter of the hole made. Thus a shot of less energy than another may perforate the same thickness of armor if its calibre is less, because it does not require to make so large a hole. Thus the 9.45-inch Krupp gun in 1879 had about the same power of perforation as the 12.5 Woolwich gun, namely, about 18 inches, and would be considered a match for the same plate.”
“If, however, armor is too hard to perforate, and yields by breaking up instead, it appears doubtful if the smaller calibre possesses any advantage over the other. The work of ‘smashing* appears to be more likely proportional to the striking energy or stored-up work. Thus, in the case above quoted, the 12.5-inch shot has more energy than the 9.45-inch shot, in the proportion of nearly 3 to 2, and might break up armor accordingly. So, again, the 100-ton M. L. gun at 2200 yards had about the same perforation as the 43-ton B. L. gun at the muzzle, namely, about 24 inches of iron. Its energy, however, is greater in the proportion of 3 to 2; and the larger projectile has this advantage with a velocity of only 1500 feet per second, while that of the smaller one is over 2Q00 feet. It is quite conceivable then that the former would hold better together, and thus deliver perhaps double the blow of the smaller one before breaking up. In such a case, then, it appears that the standard of perforation is a very erroneous one.
“It is, however, the only standard which has been definitely worked out, and on it our diagrams and rules are based. They must therefore be considered correct only when applied to cases of soft armor. Hard armor, which cannot be perforated, includes chilled cast-iron, and, in most cases, steel-faced armor and steel, though the latter may be made so soft as to approach wrought-iron, and so be perforated in a fairly clean hole. This, however, has not been the character of most of the steel plates hitherto tried. A projectile may drive its point a short distance into hard steel, but eventually it acts as a conical wedge, splitting up the plate, and the shot breaks up before the entire head enters the plate, so that the size of the calibre probably affects the problem less than the shape of the point, and it appears that the main question is that of striking energy, modified by the shot’s power to hold together, which again depends directly on tenacity of metal, and possibly inversely on some function of the striking velocity.”
Under the head of “Perforation of Soft Armor” is given an interesting discussion and comparison of the various empirical formulas which have been suggested and used, including those of Fairbairn, Inglis, Maitland, Noble and Krupp, and the author also gives an interesting table showing the measure of accuracy of the results given by the Rule of Thumb, which is that the thickness of iron that may be perforated by a shot is found by multiplying the calibre by the number of thousand feet striking velocity, with those given by Maitland’s diagram—using the various guns in the English and German services; and the conclusion reached is that under circumstances when a quick estimate of the power of the gun is necessary, the above rule will hold good without a large error.
Under the heading “Hard Armor” the author remarks:
“In compound or steel-faced armor, actual perforation has occasionally been obtained; occasionally also a steel shot has set up and driven a large disk out of a compound plate, which action may partake of the character of perforation, and its diameter may bear some relation to that of the projectile. Most compound and solid steel shields, however, and all chilled iron shields must be destroyed by fracture, the shot’s point penetrating only to a certain depth, often an insignificant one.”
"Here, then, fracture is caused by a blow delivered, as it were, on an ogival-pointed wedge, which splits the shield asunder. This action differs widely from perforation; for while in both cases the stored-up work or energy is the motive power, in perforation the thickness perforated depends inversely on the size of the hole of diameter of the shot. Whereas in destruction by fracture the point only of the shot enters the plate, and its diameter can scarcely enter into the question. . . .
“The question of fracture is a difficult one. It has been said to be altogether beyond mathematical calculation. It must, however, follow certain laws if uniformity of quality could be secured, for even steel is not really capricious. The elements certainly are troublesome ones. As to dimensions, the minimum cross-measurement is the line of most probable fracture, but bolt holes and other features have their influence. Cracking, itself, is a complicated action. Clearly the first half of a crack represents much more work than the completion of it, consequently an increase in width of plate would not probably give a plate a proportional increase in resisting power. It is suggested that the subject might be approached on a small scale, that steel bullets might be fired against small slabs of steel and chilled iron. These slabs should be sufficiently long to ensure a line of least resistance in one direction, which would probably depend on its actual dimension; a disk or any plate where the direction of the line of least resistance might probably be determined by a flaw would be the worst kind to employ.”
“By firing at very great numbers of small plates with all the conditions fixed, except the one at the moment under investigation, it is probable that something might be learned of the laws of fracture under impact. In the meantime little can be said definitely about it beyond the elementary but important fact that effect is not proportional to the shot’s perforation, but much more nearly to its total energy, a consideration that may actually affect the selection of the guns employed against hard shields on service; if, however, armor should in the long run be made hard enough to resist perforation proper, that is, perforation without breaking up the armor, it follows that the destructive powers of guns will depend not upon their power of perforation, but upon the stored-up work or energy. The value of a gun may generally, therefore, be estimated on the measure used by Krupp, that is, the energy per ton of gun. New type guns will not then benefit by the fact that the reduced diameter of the projectile demands a smaller hole in the plate. For example, the new 63-ton gun of 13.5-inch calibre of 1884 has a velocity of 2050 feet and a perforation at the muzzle of about 30 inches of iron. This will seldom apply, for it will seldom have to fire at anything approaching 30 inches of iron; the nearest approach perhaps may be found in very soft steel. The projectile has, however, a total energy at the muzzle of about 36,350 foot-tons. This will represent its total smashing power against hard armor. This is about 577 foot-tons per ton of gun, which represents the value of the gun as an investment in artillery power. If this be compared with the energy per ton of the 38-ton gun, which was 360 foot-tons, the extent of the artillery improvements in the construction of guns and burning of powder will be appreciated.”
ROYAL UNITED SERVICE INSTITUTION JOURNAL.
No. CXXVII. Machine guns in the field, by Captain Lord Charles Beresford, R. N.
Lord Beresford says, as a naval officer he feels a certain amount of hesitation in taking up a question which perhaps the officers of the Army might naturally think peculiarly their own; at the same time it must be remembered that the Navy has had more actual experience in working machine guns in the field than any other branch of Her Majesty’s service; and guns for this purpose are supplied to the naval service, but not to the Army. He describes a machine gun proper as a gun without recoil; in other words, a gun which does not require relaying after every shot; and there are two entirely distinct kinds of such guns, the one a shell-firing gun, and the other a bullet-firing or rifle- calibre gun. International law does not admit any explosive projectile under 14 ounces in weight, which would mean 1¼ in. diameter, and the weight of a machine gun throwing such a projectile would detract from its value as a machine gun, making it almost artillery. It is still undecided whether these guns are for the infantry, artillery or cavalry. Fifteen years ago the Germans said the artillery don’t want it and the infantry won’t have it. This still finds favor with many. The value of the gun as a means of attack is still uncertain, but its great superiority as a means of defence is unquestioned. It is estimated that a first-class gun is equal to 70 men with rifles in repelling an attack, so far as the number of shots delivered; and infinitely superior in accuracy, because the piece has no nerves and cannot get excited. The questions of manning and mounting the piece as well as providing ammunition were discussed. The gun’s crew must be regulated by the service intended; to work the piece requires a very few men, but to transport it and its ammunition, if no animals are used, will require a great many. The small gun when mounted on a tripod can be carried by two men.
The result of the discussion would seem to be that the guns will not take the place of artillery, but be rather an infantry arm. That the guns should be mounted on a tripod or on a carriage without limber, so that the gun may have an all-around fire over the wheels. The carriage should be fitted with shafts, that a horse may drag it when on distant service. The ammunition to be of same calibre used in the rifles of the command, and so much of it as is not carried on the carriage should be carried on pack mules or horses. (The question of supply of machine gun ammunition is one of vital importance, vide Nav. Inst. Proceedings, 7, 416.)
No. CXXX. Electricity as applied to naval purposes, by Lieutenant W. A. Chisholm-Batten, R. N.
This article gives a resume of the subject in a general way without going much into particulars. It divides the subject into two general parts: 1st. Application for general purposes; 2d. Application for war purposes. Under the former it discusses electric lighting, external and internal, the use of the telephone and of the telegraph both on board and by landing parties, electric speed and distance indicators, and the use of electricity for the propulsion and steering of boats. Under the latter head it considers the firing of guns by electricity, which it places as first in importance, and the use of electricity in firing, propelling, and steering torpedoes, in firing mines, and in detecting torpedoes. The subject is one of great interest to naval officers, and Lieutenant Batten’s article is well worth reading.
UNITED SERVICE GAZETTE.
June 27, 1885. The speed trials of the steel dispatch vessel Surprise.
These have been completed, with the following results: With forced draft, speed, 17.846 knots an hour; revolutions, 133 a minute; collective H. P., 3107.7; fuel consumption, 2.78 pounds per H. P. an hour; steam pressure, 96.6 pounds per square inch. With natural draft; speed, 16.49 knots; H. P., 2104; fuel consumption, 2.6 pounds. Each engine has cylinders 26 inches and 50 inches in diameter with a stroke of 34 inches; steam is supplied from 4 boilers at 100 pounds pressure. With the helm hard over the ship turned in a circle of 244 yards diameter in 3 minutes. An arched steel deck inch thick runs the entire length of the ship, and the engines and 8 boilers are further protected by side coal bunkers 114 feet long and 7 feet wide. The vessel is 250 feet long, with 30 ½ feet beam, 1400 tons displacement, mean draught 13 feet, and has 48 water-tight compartments. The complement will be 86 officers and men, and she will carry 400 tons of coal.
July 4. The evolutionary squadron in Bantry Bay.
“One result of the experiments, as far as they have gone, cannot but be to diminish the confidence which has hitherto been felt in the mosquito (torpedo) fleet as an auxiliary to the ironclads of the squadron. For harbor defences they are no doubt excellent; but it must be taken as proved that they are not sufficiently seaworthy to be relied upon to accompany a fleet in all weathers.” The ease with which the Polyphemus snapped the boom for the protection of the defending vessels, though strengthened by two 5-inch steel cables, was remarkable; and after such a display of power, it can be said that no fleet can consider itself protected by a boom against the attack of an enemy possessing a vessel of that type.
Explosion on board H. M. S. Valiant.
While engaged in practice with “hand charges ” containing about one pound of gun-cotton, the operator threw the charge from the stern of the launch towards the water, but in some way the connecting wire became entangled. While endeavoring to clear it, the pistol in the other hand of the operator went off and fired the charge. The entire stern of the launch was blown out, pieces of metal were buried in the bulwarks and thwarts, and a hole pierced in the side. Though none of the crew of (eight men was killed, several were dangerously wounded.
July 11.
The removal of the plates from the Leander, which ran on Hornet Rock in Bantry Bay, showed that about 50 feet of the ribs and divisional plates of the double bottom were crushed into all shapes. The first longitudinal frame was twisted and bent in every direction, and a number of the ribs were literally doubled up. There was not a crack or fissure to be seen in the plates, which were made of the best homogeneous steel. The plates that were taken off were passed through rollers and straightened, and some of them have been put back into their places in the ship. This illustrates the superiority of homogeneous steel over iron for ship construction. Another lesson taught is, that with double bottoms, the inner bottom should be as strong, if not stronger, than the outer.
Mr. Nordenfelt has applied for a patent for incorporating gunpowder as follows: Sulphur is put in solution as sulphate of carbon; this is mixed with carbonaceous matter, cotton or cellulose fibre ground to an impalpable powder. Finally a saturated solution of saltpetre is added, all in required proportions. By evaporation an almost liquid gunpowder is obtained.
July 18.
Two steel-gun torpedo boats, building at Devonport, will when completed be powerfully armed craft. The boilers and engines are to be placed on board before the vessels are launched, so that steam may be got up and the engines worked the day after they are launched. The vessels are 195 feet long, 28 feet beam, have a displacement of 435 tons and a mean draught of 10½ feet. They will carry 250 tons of coal, will develop 1200 I.H.P., and will be armed with one 6-inch and three 5-inch B. L. R., with Nordenfelts and Gardners, and will cost about $203,000 each.
July 25. The Icarus.
This sloop of the Racer class, which proved very successful in the late manoeuvres at Bantry Bay, is to be launched shortly. She is 167 feet long, 32 feet beam, with a displacement of 950 tons and an extreme draught of 14 feet 4 inches. The coal supply is 150 tons, and the speed with ordinary draft,
I. H. P. 1200, is to be 12½ knots, with forced draft 14 knots. She will carry a crew of 100 men and eight 5-inch B. L. R., four in central pivot on poop and forecastle, besides four Nordenfelts and Gardners. She has been barely a year building and will cost about #237,000.
The Lorenz bullet.
The experiments made in Germany with these balls, formed of a very thin shell of steel filled with lead, show that while there is no erosive action upon the barrel of the gun, the penetration is four times that of the ordinary lead bullet. Tungsten has been suggested as a substitute for lead in the manufacture of bullets, on account of its greater specific gravity, the ratio being as 17.6 to 11.4.
August 15. The Amphion.
This twin-screw steel cruiser will shortly be completed, and from improvements made in her armament and from her increased speed she will be much superior to her sister ships, the Mercury and Leander. She is built entirely of steel, is 300 feet long and 46 feet beam, with a displacement of 3750 tons. On her trial 6000 H. P. was developed and a speed of 18 knots. The armament consists of ten 6-inch guns on Vavasseur carriages, six in broadside and four on raised platforms on central pivots; eight Nordenfelts, four Gardners, and ten 14-inch Whitehead torpedoes. She is fitted with electric lights, has a coal capacity of 1000 tons, and her complement is 257 men. The total cost of hull and machinery is about $850,000.
August 29. The Nordenfelt submarine boat.
This Winans-cigar-shaped boat is built of plates of mild steel 5/8 inch to 3/8 inch thick. The sponsons on each side form wells for the protection of two propellers which act in a vertical direction for submerging the boat; in case of accident to the machinery, the boat being buoyant will rise. Balanced rudders are used to maintain a horizontal position, and when the boat is submerged steam is supplied by means of the heat which has been accumulated in a water reservoir while at the surface, where the steam motive power is derived from an ordinary marine boiler. Mechanical appliances cool the air, and show its life-sustaining properties; indicate the depth, and stop the vertical propellers when a desired depth has been reached, and start them again as soon as the boat rises from it; pump out in case of leakage, and lighten in case of emergency, by blowing out eight tons of hot water. There is sufficient air space for four men to be entirely cut off from communication with the outer air for six hours, though the longest time that the boat has remained totally submerged is an hour. The boat has made a trip of 600 miles on the surface, having gone 150 miles without recoaling; completely closed up, it has been driven 16 miles by the heat from the hot water reservoir, the speed being 3 miles per hour. Though the boat is intended to withstand the pressure at a depth of 100 feet, the greatest depth at which it has been worked is 16 feet. As a means of defence against surface boats it is intended to carry a 1½-inch single barrel Nordenfelt shell gun.
September 12. Coast and harbor defences.
Messrs. Seath & Co., of Glasgow, have submitted a plan of a vessel for harbor defence, to be 150 feet long with 30 feet beam, divided by three fore and aft and eight thwartship bulkheads into thirty-two water-tight compartments. The bottom part of the shell describes a segment of a circle from stem to stern to allow the vessel to turn upon her own axis. Above the water line is a steel belt two inches in thickness, tapering upwards and downwards to deflect projectiles. The armament is to consist of two heavy immovable guns, one forward and one aft, to be trained by the helm.
September 19. The Benbow.*
This vessel will draw 26 feet 3 inches forward, and 27 feet 3 inches aft; the coal capacity is 1200 tons, and estimated speed 16 knots. The thickness of the armor plating is, on the sides 18 inches, bulkheads 16 inches, barbettes 14 inches and 12 inches, conning tower 12 inches and 9 inches, armor tubes 12 inches, screw bulkheads 6 inches, decks, 3 inches and 2½ inches; skin plating, 1 inch; the wood backing, of teak, 15 to 12 inches. The cost of hull and fittings is $2,300,000, of machinery, $518,000; complement of men, 455.
The despatch vessel Mercury will be armed with thirteen 5-inch B. L. R., ten broadside, two forward, and one on the poop.
September 26. The Gatling gun accident.
While the vessels of the Channel squadron were engaged in exercising with machine guns, an explosion took place on board the Sultan, in the hopper of a Gatling, by which two men were badly hurt. [No details are given, but the gun and hopper were sent to the Admiralty, where the cause of the explosion will be investigated.]