A Machine-Shop in a Diving-Bell
��A DIVING-BELL in a large sted tank filkxl with clear water was exhibited in a New York store recently. The tank was fourteen feet in diameter and ten in height.
Suspended from a stanchion overhead was an iron sphere about four feet in diameter. It hung from the stanchion by chains and could be raised or lowered by means of a triple expansion block and tackle. A stout, well insulated electric cable ran into the sphere and disappeared over the rim of the tank to a strange-looking switchboard. Protruding from one side of the ball and equally distant were four powerful electromagnets. The flat surfaces, or "heels" of these were parallel. Fac- ing them was a thick steel plate suspended in the water. From the external switch- board, electric current was sent through the cable and into the electromagnets. They exerted a pulling force of four tons each which drew them and the sphere to which they were rigidly fast- ened, against the steel plate. The steel plate represented the steel side of a sunken ship. Another switch was and a half-inch steel drill truded from the sphere between the four magnets commenced to turn until it penetrated the steel plate. Another switch was thrown on. The drill with- drew from the hole it had bored and wormscrews commenced to revolve which shifted the position of the ball slighth', and in a very few minutes another hole was drilled.
Under actual working conditions, this sphere would be used to carry two men to the sea bottom, who would attack the side of a sunken steel or iron ship exactly as the miniature sphere attacked
��the steel plate in the diving tank. In the demonstrating apparatus, the stan- chion represented the sea barge from which the hollow iron ball carrying the two workmen and their equipment would be lowered to the depths in the vicinity of the sunken ship, through the sides of
���FOR Shifting. POiillCNS or MAGNET J
��The steel plate in the tank represents the steel side of a sunken ship through which holes will be drilled for grappling hooks
��thrown on, which pro-
��which holes would be drilled as the first step toward raising it to the surface for salvaging.
When sufficient holes were drilled strong hooks would be inserted to which would be attached pontoons. When enough hooks had been inserted and enough pon- toons attached to them, the water would be pumped from the pontoons from above. The ship, theoretically, would rise to the surface, and could then be towed without further difficultj- to the nearest dock.
While the miniature apparatus per- forms admirably, the "life-sized" diving sphere has not yet been given a trial.
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