Rules Governing the Competition for the $15,000 Prize Offered
within the compass of modern engineering, the wreck of the ship will be raised, and the entombed bodies of the sailors, who were lost over a dozen years ago, will be given honorable burial in the National Ceme tery at Arlington. On the front page of this issue we ill. ustrate a prac tical method by which it is proposed to do this work. The plan was worked out by John F. O'Rourke, presi dent of the O'Rourke Engineering Construction Com pany, who has submitted the proposal to Acting Secre tary of
... cting Secre tary of War Oliver in a letter which describes fully the method by which the work would be done. Briefly stated, the plan contemplates the building of heavy pile wharves along each side of the wreck :md the sinking between the wharves and the ship of pneumatic caissons. Heavy steel cables would be slung underneath the ship's bottom, and, by means of powerful jacks carried upon the caissons, the wreck would be lifted clear of the wat";. If the O'Rourke method be adopted the first opera tion will be to construct, parallel with the sides of the ship and about twenty feet therefrom, two ordi nary pile wharves. '!'hen, in the space between the wharves and the ship, twelve pneumatic caissons, of which there will be six on each side, will be sunk by the ordinary methods to a depth of about ten feet below the bottom of the "Maine." At every four feet along the cai�sons will be erected a stout A-frame, strongly braced and guyed, with double columns, which will be built up about thirty feet, and will be finished at the top with a massive casting carrying a screw jack of at least one hundred tons capacity. At each' pair of opposite frames will be' a pair Qf steel cables of different sizes, the cables on one side being of about two hundred tons capacity, and the other, on the opposite framework, being a small three quarter-inch hauling cable. These cables will be car ried down outside the caissons and underneath their cutting edges, the ends being coiled in the air cham bers before the sinking is begun. After the caissons have been sunk to the required depth, a small pipe will be pushed horizontally through the mud from one air chamber to the one on the opposite side of the wreck. Through this pipe the end of the small cable will be passed to the opposite air chamber; after which the pipe will be pulled back into that air chamber over the end of the cable, leav ing it lying exposed in the mud. The end of the big cable will then be attached to the hauling cable, and the former will be pulled out from under the cutting edge, and under and around the "Maine" to the top of the opposite caisson. When this has been done, a series of plow steel cables, each of two hundred tons capacity, will have been passed entirely around the bottom of the Maine, with their ends carried up to the caissons on each side. The combined strength of the cables will be' equal to carrying four times the weight of the battle ship. It should be mentioned that a strongly-braced floO!" will be built above the wharf piling, and carried en tirely across the tops of the caissons, and that each series of caissons, with its accompanying wharf, will thus form a structure of great rigidity and large bear ing capacity. The screws of the powerful jacks at the head of the framework end in an eye bar head, . and clamps are provided to grip the cables, which are finished in two similar eye bar heads, which are pinned to the screws of the jacks by a 3�-inch pin of over one hundred tons capacity. When the screw jacks have all been connected to the cables, a strong tension will be taken upon the latter by means of the jacks, and then an amount of water corre sponding to the wei ght of the "Maine" will be pumped out from the cofferdams of the caissons. The buoyancy thus given to the caissons will prepare them to receive the weight of the "Maine" without imposing any addi tional weight on the mud bottom upon which the caissons rest. The latter are made of sufficient size and strength to contain 50 per cent more weight of water than the ship weighs, so that there is a margin of about 3,000 tons of water to draw upon, should it be required. The caissons being now prepared for receiving the weight of the ship, the bottom of the ship will be loosened from the mud by means of the water jet, small pipes being driven down alongside and under neath the hull, through which water will be forced under pressure, destroying the snug contact between the mud and the hull (the so-called suction) and so putting the vessel in condition for the final lift. The first operation will be to manipulate the screws on the lower side of the vessel until she has been brought around to an even keel, and leveled up fore and aft. Then the screws on opposite sides will be slacked off in pairs, set down to their fullest extent, and reclamped Scientific American" on the cables when everything will be ready for an upward lift of about ten feet. This operation of set ting down the screws and lifting the ship will be re peated until the vessel has been lifted clear of the water. The next step will be to build a strong platform or deck between the bottom of the ship and the water, thus providing a drydock of ample strength, which will afford facility for the examination and re pair (if so determined upon) of the hull. In speaking of his method, Mr. O'Rourke says: "The wharf building, the caisson sinking, the passing of pipes between air chambers, the placing of cables underneath and around the ship, the construction of the lifting structure, and the fitting and operation of the screw jacks are all operations well understood, easily carried out, and independent of any questions of depth of mud or condition of the ship. The mud, however deep, does not complicate the question or add materially to the cost; and should there be ob structions at any point preventing the passing of the cables, tunneling to and removal of the obstruction is. a simple matter. Damages to the ship, however great, would not prevent its being brought up intact because of the distribution of the weight and the flexibility, contiguity, as well as rigidity, of the means employed." With tb'l ship thus placed upon a stable platform, not only would it be possible to recover the bodies of the men who perished in the disaster, but in all probability the cause of the explosion could be de termined beyond all question of doubt.