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which handle material under all imagi- 34 feet between the centers and has a
nable circumstances where the loads do swing of 125 inches.
not exceed several tons.

Pneumatic Devices
Machine Tools

American shipbuilders, who were the Powerful machine tools constitute originators in introducing pneumatic another of the utilities which are con machinery in shipyards, are yet well in tributing largely to the advance of advance in the utilization of this form American shipbuilding. A review of the of apparatus. Indeed, within little more facilities in some of the larger plants dis than half a decade, there has been decloses the following: A hydraulic man veloped in American shipyards a system

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hole punching machine, which is ac of power riveting which surpasses any-
counted the heaviest in the United States, thing previously attained anywhere in
and which, with a pressure of 1,500 the world. At first an attempt was made
pounds, punches a manhole 18 by 27 to use pneumatic compression riveters
inches in size from plates 34 inch thick'; similar to those in use in many bridge
32-foot bending rolls, which are the shops; but it was soon demonstrated that
largest in the world; some of the heaviest their great weight for the large gaps
cutting shears ever made, with maximum necessary in shipbuilding made it im-
dimension of cut of four inches; 36-, practicable to handle them with either
60-, and 84-inch planers; a wall planer facility or economy in the case of ships
measuring 22 feet plane by 22 feet slot, on the stocks.
which has no parallel in the world; and The shipbuilders, however, knew from
a 125-inch shafting lathe, which will take experience, of the value for chipping and

calking of the pneumatic hammer, con plating so heavy that to draw it up resisting of a piston rapidly reciprocating quires rivets too large to be properly inside of a cylinder, and striking the end driven by hand. From an economical of a chisel ; and this apparatus was grad- standpoint, the power riveters perform ually adapted to the driving of rivets. wonders. In deck and tank topwork, for

instance, three men and a heater boy will drive from 800 to 1,000 rivets a day. Not only is the whole operation of driving a rivet completed much more quickly than by hand, but it is done so expeditiously that the rivet has not lost its heat ere completion, and consequently there is gained the benefit of the resulting contraction, which, as the rivet cools, draws everything together with firmness.

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PNEUMATIC STEEL CUTTER IN OPERATION.

IRON CORNER CUTTER.

Shipbuilders in this country who have made a careful computation, figure out that machine riveting, adding the cost of air, repairs, etc., effects a saving of from one to two cents per rivet over piecework prices for hand riveting, the degree of economy depending upon the location in the ship, and averaging fully 1/4 cents. In the shipyards on the Great

The adoption of these power riveters came just at the most opportune time, for the increase in the size of ships of late years has involved the necessity for

Lakes, where pneumatic machinery of this the limit for reaming and tapping being class is used very extensively, the saving 1/2 inches. Such a drill requires about on an ordinary lake steamer of 4,000 tons 25 feet of free air per minute to operate is from $4,000 to $5,000. One machine it at 80 pounds' pressure. Side-light cutwill not infrequently drive 450 78-inch ters, deck-boring machines, and other rivets in a single day. At the regular

At the regular pneumatic appliances also have place in hand-work rate, this would involve an the equipment of the modern shipyard. outlay of $15.75; whereas, with the ma Some yards have in use at one time as chine, the cost is but $5.50, including the many as 400 portable riveters, calkers, wages of operatives and the cost of drills, etc. Power for the machines is power.

Another class of pneumatic tools in use in shipyards consists of chipping, calking, and bending hammers, machines which range in weight from 7 to II pounds and which have a stroke of from one to four inches at speeds varying from 3,400 to 2,200 strokes per minute according to size. These hammers require 20 feet of free air per minute, and work at a pressure of from 70 to 80 pounds. The heavy chipping hammers weigh fifteen pounds, and attain a speed of 1,200 blows per minute for the 7-inch stroke. Most powerful of all the hammers is what is known as the "9-inch stroke riveting hammer," which has a speed of 905 strokes per minute. A pneumatic holder

PNEUMATIC DRILL IN OPERATION. on is in use in many shipyards, instead of the ordinary bar, for holding up the

furnished in most instances by a 21/2head of the rivet. It can readily be put inch main ; and an air pressure of at

least 110 pounds is carried, supplied by an air compressor capable of delivering, say, 5,000 cubic feet of air per minute.

Machine and Brass Shops The machine and brass shops and other under-cover portions of modern American shipyards have within the past few years shown vast improvement in equipment and arrangement.

An ideal structure of this kind—the newest shop at the Cramp plant-is 335 by 143 feet, and of steel-skeleton framework construction. The floor load in the second story is 400 pounds per square foot, while the third floor is designed for a load of 350 pounds per square foot. The structure has a

main central traveling-crane runway, into position, and presses the rivet against served by two 50-ton electric cranes, with the sheet with a force of 1,200 pounds a span of about 57 feet, center to center when 100 pounds of air pressure is used. of supporting girders. On either side

Several styles of pneumatic air drills of the main central portion are galleries are in use in shipyards; but a machine 42 feet wide. The floor space in the that is typical in all respects weighs 35 lower story of both wings is served by pounds, and will drill in cast iron up to electric cranes of from 10 to 30 tons 2 inches, or in steel up to 158 inches, capacity.

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PNEUMATIC RIVETER IN OPERATION.

Some idea of the magnitude of a pres

Use of Electric Power ent-day shipyard of the first class, may In conclusion, a word should be said be gained from the fact that the Cramp regarding the extent to which electrical yard at Philadelphia represents an ex energy is displacing steam power in the penditure of more than $7,000,000; and operations of the more important shipthe great shipyard at Newport News, yards. Not only are almost all the cranes, Va., on Hampton Roads, involved an large and small, electrically operated, but even greater outlay. In the laying out almost every one of the big machine of all our big shipbuilding plants, heavy tools is impelled by an individual motor, expenditure has been made to secure con thus insuring a great saving, since the venience, speed, and economy in the con power need be turned on only when duct of operations--a continuous, unre actually needed. The electrical outfit tarded movement forward of the material which at the Newport News yard furfrom the time it enters the yard in raw nishes power for running all the mastate until it is ready to leave as part of a chines in the shops and also supplies curcompleted ship. To this end, buildings rent for the 2,500 incandescent and 150 have been grouped-at the Cramp plant, arc lights in the plant, consists of three joiner, pattern, machine, and erecting 600-K. W. generators driven by three shops are combined within the shelter of compound engines; two 125-K. W. genone immense structure 1,164 feet in erators driven by one horizontal-comlength—and all material is conveyed by pound engine; and two 75-K. W. genshort hauls.

erators driven by simple engines.

The Machinery of Modern Warfare

No. II.

Ingenious Devices that Increase the Efficiency of Peacemakers

By RUTLEDGE RUTHERFORD

T

IIIS IS AN AGE of new ma durance of the English, but incited the chines of war. In the last issue Englishman's wits, awakened his latent of THE TECHNICAL WORLD were mechanical genius, and brought forth

described several of the new new inventions that have surprised the weapons and methods of destruction that world. In Thibet the British are now were making their appearance in the Jap- testing for the first time several marvelanese-Russian war. But these are not ous new contrivances that had their inall. The fever to invent devices that will ception in ideas originating in South destroy life and property in the quickest Africa. and most wholesale manner, is catching ;

The Hyposcope and nations seem to vie with one another The very newest of these contrivances, in their efforts to produce the most deadly and one that has a most promising future, weapons. Indications are that the next

is a new rifle-sight that enables a soldier decade will witness radical changes in the to shoot at the enemy while the marksfeatures and methods of manufacture of man hides behind a rock or tree or otherall war materials.

wise completely obscures himself. This The new

era of fighting devices is regarded as war's masterpiece of prothrough which we now passing, tective mechanism, and is causing a great seems to have had its birth in the recent amount of comment in Europe. The South African war. That stubborn strug sight is called the “Hyposcope." The gle not only tested the courage and en pictures of the rifle with the new arrange

are

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SOLDIER SIGHTING RIFLE BEHIND PARAPET, BY MEANS OF HYPOSCOPE.

moving the rifle from the rest or exposing any part of the marksman to the enemy.

An ingenious arrangement of mirrors is the basis of this new and remarkable invention. The mirrors are contained in a light, strong metallic case, which is easily attached to the rifle and which enables the marksman to take aim from behind an embankment or other obstacle, without exposing himself. When first tested a short time ago in Thibet, the hyposcope fully demonstrated all that was ever claimed for it. The Thibetans, falling before the fire of the unseen foe, were completely nonplussed and fled in dismay, declaring that the very rocks and hills rained death on them when they went forth to fight the British. The result has been to create an uncontrollable superstition among the Llama's forces that they are the objects of Divine enmity and that the unseen powers of Providence are fighting against them.

The hyposcope, it is claimed, can be used at any range shown on the back sight of any rifle. Shooting may be as accurately continued without an ordinary back sight as with one—which is equivalent to an additional back sight, should that on the rifle be rendered useless. A trustworthy telescope is thus also added. The elevation of the hyposcope can be accurately and immediately effected by

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