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Show I HOW IS A SUBMARINE OPERATED? The modern submarine, which destroyed de-stroyed three large British cruisers in the North Sea, Is described in an article in the Scientific American, as follows: The form of the hull is generally cigarshaped it is built or the very best quality of mild steel, and the workmanship is of the high est order for the reason that every .seam and rivet must be perfectly tight, in view of the service which the boat Is called upon to perform Not only do vessels of this type undergo un-dergo all the stresses of sea and I weather which other vessels are sub-1 jected to, but in addition they are required re-quired to navigate at considerable depths below the surface of the water At these depths the pressure of the water is great, so that the hull must be made sufficiently strong to withstand with-stand it. For submerged work large storage batteries are provided which furnish energy sufficient to drive the boat from ten to eleven knots for a period of over an hour The same electrical enerey will drive her at a lower speed for a much longer time. There are two distinct conditions in which the boat may be used. In the first, commonly known as the surface condition, the boat is prepared for rruislng a considerable portion of her hull is above water, a removable navigating bridge is in place. an the Is driven by large, powerful, In teinnl-combusiion enni1"1' 1'nde these conditions she is managed It about tbe B&me way as any vesse built, to run upon the surface Kt for sea-going qualities, the lubina rmeR of our own service have beer found in practice to he excellent In ordinary weather they are fully j s comfortable as any surface craft ol the sarm? dimensions, and even In the heaviest weather they are enttWO seaworthy Th" second distinct condition ists when the lat is submerged To pass from the surface to the sub merged condition, certain valvis i" the Interior of the boat are opened. This allowa the water from the. sea to run Into great tanks built within the boat, and thus virtually sink her. These tanks are closeh gatred, ao that Just the required amount of wa tor Is takn In. Under normal conditions, condi-tions, when the boat Is at rest with the ballast tanks filled, she. will have n few hundred pounds reserve buoyant buoy-ant y, which is repreaentod by th top of her conning tower protruding abovM the water If desired, this buoyancy may be entirely destroyed by admit tliiK a small additional amount ot water, equal in volume to the volume of that pert of the conning tower above water. While In the submerged condition, all communication with the outside atmosphere Ik necessarily cut off. Tbe crew then breathes the air originally contains) within the huii which is sufficient to support life with comfort for at least twenty-four hours But. In addition to the air thus contained con-tained the boat carries a large supply sup-ply of compressed air in steel flasks, which, if used for breathing purposc-s. would he sufficient for a number of days. After having brought the boat to the submerged condition In the manner man-ner above described, powerful electric motors are started by throwing in a switch These motors derive their onergy from storage batteries contained contain-ed In the boat, and drive the propel lers The same 6torage batteries furnish fur-nish current for numerous auxiliary motors used for pumping steerlug, handling torpedoes, etc. -oo |