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The inherent directive force of the Howell torpedo quite obviates all these difficulties. No projecting spoon is required on the discharge tube, the aim is direct, and no heed need be taken of rolling, heeling or wave surface.

For straight-ahead fire above water, the chances of being overrun are the same in both the Whitehead and the Howell, as in both the driving power of the screws takes effect at the same time. It is an odd accident that in under-water fire the Howell has the advantage of the Whitehead in straight-ahead fire, and the two are equally handicapped in beam fire, whilst above water the conditions of advantage and equality of the Howell are reversed.

THE ELWELL LAUNCHING GEAR.

The launching gear designed by Mr. Elwell, the Superintending Engineer of the American Branch of the Hotchkiss Ordnance Company, possesses a striking feature in the application of the expulsive force. The medium of discharge is gunpowder, but it is so applied that the explosive shock is cushioned against the torpedo, no fouling or solid particles enter the discharge tube, and although ordinary black powder is used, the discharge is practically noiseless and smokeless. The cartridge itself is also in the simple form of ordinary metallic cartridge case ammunition.

Discharge tubes differ in general arrangement, depending upon their emplacement; that is, whether under or over water, and whether fixed or pivoting. With the exception of the accessory features, however, a description of one apparatus will serve for all, as with all gears used for the Howell torpedo every effort is made to maintain as close a similitude as possible.

THE CENTER PIVOT LAUNCHING TUBE.

Plate V. This gear is designed for open-deck emplacements, where all. around fire is permissible.

The discharge tube is of bronze, bored to a diameter five hundredths of an inch greater than the midship diameter of the torpedo (14.25 inches for the general service torpedo). It is mounted upon a low, broad cone, A. A., whose base rests on a bed-plate, B. B., bolted to the deck, the two being held together by a stout clip-ring, C. C., so that the cone is free to revolve. The interior of this cone may be fitted with a rack and gears, so that the tube may be aimed from a conning tower if desirable. A shallow groove, S., Plate III., is cut the full length of the tube along the bottom of the bore to carry the guide-stud of the torpedo. The rear end of this tube is closed by a door, D.D., hinged to swing laterally, its inside edge being coned and ground to close air-tight. A steel cross-bar, E. E., with a tightening screw, F., through its center, is carried by the same hinges as the door, the free end of the bar being held by a stout bronze loop, G. G., when the door is closed. To lock the door, it is closed, the loop is swung over the end of the bar, and a few turns are given to the tightening screw.

Two brass air tubes, H. H. H. H., are secured to the main tube underneath, one on each side, being connected together at the front end by a cross-pipe, I. The tube on the right-hand side, cal the firing tube, has screwed to its rear end a small bronze breechpiece, K. K., which is chambered to carry an ordinary metallic cartridge case, and has a simple breech-block, L. L., in which is fitted a hammer, sear and main-spring. The weight of powder used is less than half a pound, with which a discharge speed of over thirtyfive knots can be obtained for a torpedo weighing nearly five hundred pounds. The front ends of both air tubes are closed by screw-caps, M., that may be removed whenever necessary to sweep out the tubes. It will be noticed that the forward end of the firing tube is extended well beyond the cross-duct, 1. This is done in order to form a lodgment for bits of wad or unburned grains of powder that by the explosion will be driven past the duct and be caught and held in this space, precisely as is the case with the cindertrap of a locomotive engine.

The rear end of the left-hand pipe, called the compression pipe, connects by an elbow with the main tube. Around the rear of the main tube is secured a hollow strap, N. N., into which the elbow of the compression tube opens. The wall of the tube underneath this strap is pierced all around with small square ports cut at an angle, such that the blast of air created by the explosion of the charge will be directed against the door of the tube first, instead of being taken directly on the tail of the torpedo. The air pressure thus created in the main tube drives the torpedo out. At a speed of ejection of about thirty-five knots, a torpedo discharged at a height of about five feet will take the water fully thirty feet from the ship's side.

It is well at this point to call attention to a feature of torpedo use of great importance as affecting over and under-water discharge, that has hitherto not received noteworthy attention. A ship going into action probably will find it necessary to use her net, and if she is only provided with under-water tubes, all her torpedo fire is cut off by the net, whilst if she has tubes above water, she may discharge clear over the net.

The Dow motor is attached to the main tube on its right side, a hole being pierced through in the clutch-line. The steam pipe, 0. O., and the exhaust pipe, P., to and from the motor, are carried down into the supporting cone, where a junction box is made, so that the steam pipe goes through the deck inside of the exhaust. This junction is swiveled to permit the system to revolve.

A throttle valve, with a hand-wheel, R. R., gives steam, which is controlled by a regulator valve, S., and there is also connected to the throttle an automatic cut-off.

It is of great importance that, once the torpedo is in the tube in place, the work of clutching, spinning up, unclutching, cutting off steam, freeing the torpedo and discharging it, should all be done in a simple manner, quickly, and with absolute certainty of the proper succession of movements. This work is almost entirely automatic, and is done in the following manner: The small box, V., is a steam cylinder whose piston projects up through the main tube into and filling the slotway for the torpedo guide-stud and forming a stop. This piston is held up by a spiral spring underneath it. To load the torpedo into the tube it is simply necessary to push it in until its guide-stud brings up against this stop, and then close and fasten the door. The clutch hole in the torpedo is then directly in line with the motor clutch, and the moment that these clutches are thrown in action, the torpedo is held firmly against all movement.

A long rod, W.W., performs the work of clutching, disconnecting and firing. The torpedo being in its tube, the powder charge may be inserted. Lift the small spring latch, X., open the breech, and insert the cartridge. It is to be remarked that unless the torpedo is clutched up ready for spinning, it is impossible to cock the hammer, and unless the torpedo is entirely free to leave the tube, it is impossible to fire. The action of firing itself is automatic and is controlled by the lever, Q. By pulling back on the handle, Y., the long rod, W.W., is drawn to the rear, clutching the motor to the torpedo, and bringing the lever, Q., into position, so that the movement of closing the little breech cocks the hammer. If the throttle valve be now opened, steam is given to the motor, and the fly-wheel will be spun up, it being possible to so set the regulator valve that the wheel will run at any desired speed of revolution.

Discharge is operated in the following manner: A small box, Z., contains an arrangement by which a small steam valve may be operated either electrically or by a firing laniard. The valve works instantaneously, and admits steam into the small pipe, a. a., communicating with the stop-pin. Steam coming on the upper side of this little piston forces it down so that the pin comes clear of the guide-stud on the torpedo, leaving it clear to leave the tube. As this piston descends, and after withdrawing the stop, a port is unmasked, admitting steam to the pipe, 6.b. 6., passing to the cylinder, T. T., whose piston is attached to the long rod, W. W., driving it forward. As the rod moves forward it first unclutches the motor, then cuts the steam off from the motor, and finally, at the end of its course, trips the hammer and fires the cartridge. Thus all the movements are performed automatically, and they can only occur in their proper succession. The entire time from pulling the firing laniard until the torpedo leaves its tube is but little over one second, most of this time being taken by the torpedo itself gathering movement.

(COPYRIGHTED.)

U.S. NAVAL INSTITUTE, ANNAPOLIS, MD.

MARCH 1, 1890.

DESERTION, AND THE BERTILLON SYSTEM FOR THE

IDENTIFICATION OF PERSONS.
By LIEUTENANT ALEXANDER MCCRACKIN, U.S. Navy.

The subject of desertion from the army and navy has been discussed by many persons, and the causes assigned for desertion, with the methods proposed for its prevention and punishment, have been almost as numerous as the number of writers.

It may be taken as an axiom that desertions will always occur. Cases are on record of officers deserting, and the writer has questioned an enlisted man apprehended for desertion, who admitted that he had been well fed and clothed, well treated, had received plenty of liberty, that he had no real cause of discontent, and that he had previously deserted from the Marine Corps! No doubt there will always be such men.

It is idle to write of the evils of desertion and its punishment when wholesale amnesties to deserters are made, and when such principles are promulgated as these by a Senator who lately wrote of desertion as being “an offense which evidences no lack of patriotism and involves the least possible moral turpitude"!

If desertion ended a man's connection with the navy the latter would be the gainer, but unfortunately the deserter thinks it is quite the proper thing to go to another ship, re-enlist under a different alias, stay in the new ship long enough to once more become a factor of discontent and disorganization, and then desert again, and so on. Men who have been dishonorably discharged adopt the same course.

As, probably, no humanitarian would desire to thus burden the service, the only question now left of the whole subject of desertion is, how shall the Government be protected from such frauds ?

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