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Show ibFATH UNDER SEA! - Here's How Subs ABob for Their Prey 3 Sectional diagram of a torpedo. (TaTitcopltY"" Short Way Anf nnT ( Aft . . Torpedo .v, t Conning Dckl Torpdo j Ewopo 1 Room ' 1 Tower gun I Hotch ) notch ICr ; f'"' "fH - ' K Control j Wotorf ,'.T . 7 Room boHotj j Borteriet j j ' -Z7"-T v. " Torpedo Torpedo . t Quortew Quorter Room fobee J WASHINGTON The first few" weeks of the war abroad proved the submarine the. moat potent weapon in naval operations. Because Be-cause of Its comparatively small siae. It Is easily manageable: because be-cause of Its destructive torpedoes. It can sink a Una vessel before the victimized captain Is awara of an enemy craft In the vicinity. A submarine moves slowly 15 to 23 miles an hour on the surface, 1 to 10 miles submerge- Its value lies In Its ability to maneuver and remain hidden until Its prey Is in strikinc distance. Then, raisinc and lowering the periscope, the sub "bobs" for its victim, until the torpedo tor-pedo Is driven home. The U-boat Is propelled by two powerful Diesel engines, which also generate electricity lor storage batteries to run electric motors for underwater travel. Most underwater craft can remain re-main beneath the surface 18 hours without drawing on reserve oxygen. oxy-gen. Normally, they seldom stay down longer than two or three hours at a stretch. In the more recent types native oxygen will keep the crew alive up to -65 hours. Submarines are built from 350 to 2500 tons, costing from about $2.-' $2.-' 000.000 to S6.000.000. Moat popular ; stats are 250, 500 and 750-ton boats. Cu Kaage Far Freea Base ? The 750-ton craft can crutae as i far as 3750 miles from its baas of supply. The 500-ton submarine has : a cruising radius of 2500 miles and - the small boat is used only for j coastal operstiona f Most of Germany's sucrns Is attributed to 500-ton and 750-ton craft, although larger modela are in service. Taa United States navy k in some submarines there are as many as three periscopes to enable officers to watch more than one ship. Perkwepea Give Oead Visibility With the periscope four feet above the water, the commander can sight a ship 1-3 miles away. If the ship has a 100-foot mast it can be sighted as far as 13.8 miles away. This range Increases as the periscope is raised. If the periscope is 15 feet above the surface the range Is more than 15 miles: ' In war, when a vessel is sighted, the skipper shouts orders to submerge. sub-merge. A siren is sounded, hatches closed and ballast tank valves opened. Commands are relayed by electric light signals. The commander -bobs" his periscope per-iscope up and down, never more than four feet above the waves. The "bobbing" cuts down the slender slen-der chance that the sub will be sighted before the commander wishes. If the vessel is an enemy the tor-J. pedo is fired. At close range they seldom miss. Each shot costs about saooo. The torpedo Is propelled through the water by a turbine and has a rudder which will guide it In aa arc of at least 90 degrees. Thus, a torpedo may be fired from' sr submarine lying parallel to its victim. ... Torpedoes usually are loaded with TNT or cordite, set to explode ex-plode after the torpedo has drilled a hole Into the boat, not " f,rlt contact -Torpedoes can travel five or six miles. . . ' - The 750-ton submarine mounts six 21-lncn torpedo tubes, four in the noae and two in the tail. The 500-tonner has five tubes, four in front and one aft; and tha coastal boat carries three tubes, two In front and one In back. Each submarine is supplied with about three torpedoes for every tube. Submarines carry one or two three or four-Inch deck guns. Guns are sealed when the boat ducks under. built a few underwater boats of 2300 tons: but navy experts said the best type Is between 1300 and 1500 tons. A 750-ton craft Is about 230 feet long. It Is 13 feet wide and 20 feet high. The 500-ton model is about 200 feet long. 13 feet wide and 20 feet high, and the coastal boat about 130 feet in length, 12 feet in width and 13eet In height Moat of the ship Is filled with engines, torpedo tubes, Instruments, Instru-ments, safety devices and oxygen and water ballast tanks. The crews of 25 to 50 man live where they can be crowded in. Usually five or six officers are aboard. The men sleep In shifts in bunks in tha maze, at valves and levers. They eat where they can find a place. A submarine commander usually has a good Idea where he will find prey through a coordinated system of wireless reports, aerial reconnaissance recon-naissance and use of sound detectors. detec-tors. . - Diagrammed pbatogrspk shewiag hew a sub is eenstructee. ' -a J ' - ' |