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Show WHAT DEPTH BOMBS CAN DO In tho last Scientific American is an Illustrated article on the depth bomb which is now being employed extensively exten-sively in fighting the submarine. After stating that the destroyer and trawler are the most effective enemies of the U-boats, the article tells of tho depth bomb as follows: There is just one device needed to enable tho destroyer to rid the seas of the submarine pest in short order; for if someone will only produce a sound detector of sufficient range to enable a destroyer to find and follow a submarine when it Is submerged, the : thing would be done. For the submarine subma-rine is primarily a surface vessel in fact, It spends 90 per cent of its time on the surface. Its period of submergence sub-mergence in deep water Is limited; and whenever a submarine Mint wnn under observation through listening devices came up, the destroyer would have It. We Illustrate In this chapter a weapon wea-pon of which much has been heard during the past few months the depth bomb. The depth bomb can be made in any size desired, and it is probable that the average type In use carries about 250 to 350 pounds of T. N. T., which is about tho charge of the modern torpedo. The effectiveness effective-ness of this instrument consists In the I fact that it does not by any means have to hit the submarine -to destroy I IL Its dostructlveness is based upon luiiuuiiivuMu njiiL waier is incompressible, in-compressible, and thnt tho shock of detonating a mass of high explosive under water Is felt lmmediatelv in all directions the effect diminishing, of course, with the distance from the bomb. It has been stated by Hudson Maxim that four cubic feet" of T. N. T. at the moment of detonation produces pro-duces 40.000 cubic feet of gas. Now, when a mine, or bomb, or torpedo war-"head war-"head Is detonated the expanding gases seek the line of least resistance. In the case of a torpedoed ship, this lino leads into the hollow Interior of the ship, the incompressible- water forming form-ing an abutment in all other directions; direc-tions; but when a mine or depth bomb Is detonated the line of least resistance resist-ance is upward; and tho gases cut their way quickly to the surface, carrying car-rying a foundation-like mass of water to a great height into the air. If the explosion takes place at a considerable consider-able depth, however, the resistance to the upper escape of tho gases is great-or great-or and the shock transmitted through the water In all directions is proportionately propor-tionately increased. We illustrate this tendency; falling to blow up tho surface sur-face of the ocean, the bomb must blow in the submarine. The destructiveness of the bomb against the submarine will depend upon two things; first, the depth at which it is detonated, and second, tho distance from the bomb to the submarine. subma-rine. Manifestly, then, it is advisablo to detonate the bomb below the sub- m marine as the shock transmitted will j be proportionally greater than if it J were above it, other thlng3 being equal. As to the distance at which an explosion would bo absolutely destruc-1 tive, rupturing tho plating and sinking the submarine, Hudson Maxim writes us that If 500 pounds of T. N. T. were exploded deep under water within 125 feet of a deeply submerged submarine, it would completely destroy IL Smaller Small-er charges would, of course, have to be detonated proportionally closer to the submarine to secure destructive action. oo |