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October, 1910 TAe Marine Review 395 A ONE HUNDRED-TON FLOATING CRANE HE. operation of a crane, whether it be an 'ordinary . hand crane, an electric overhead traveling crane or a locomo- tive crane, is always interesting. Possibly it is the great utility of this class of machines which makes them so _ fas- cinating to us, or perhaps it is the perfection and simplicity of their mechanism which gives them their By Wa ter G. STEPHAN. used on land can usually depend upon a solid foundation for support, but the designer and builder of this mon- ster marine crane, the Wellman-Sea- ver-Morgan Co., Cleveland, was con- fronted with a very complex prob- lem, which involved. questions of sta- bility, with its related problems of center of gravity, metacenter, draught and maximum allowable inclination. The recent elaborate tests made by the government engineers have proven conclusively that the crane is excep- FLoaTiInG CRANE IN WorKING Position AL charm, Certainly, cranes now per- form much of the work formerly done by the main strength of. many hands. One of the most interesting recent developments in crane construc- tion is the 100-ton floating crane just completed for the Bremerton Navy yard at Puget sound, Wash. It is the most interesting because It is believed to be the largest crane of its kind in the world, the next in size being the crane "Hercules," which Was built to lift 100 short tons, while the crane which is the subject of this article is designed for 100 gross tons. The designer of a machine to be ----- Cleveland, tionally stable and capable of handling more than the specified loads. The loads accompanying photograph gives a good idea of the construction of the main framework and will illustrate the uses to which the crane is to be put. It is shown in position ready to un- load part of the machinery of the cruiser Washington. The government specifications called for a structure to be mounted upon a floating pontoon, and intended for lifting and moving guns, turrets, ar- mor plates, boilers and other materi- als to and from cars, wharves and ships at the Puget sound navy yard It must possess in a Bremerton. & 7 i afety, stability and ease high degree s of manipulation. The Pontoon. The pontoon which supports the main frame is built entirely of open- hearth steel, and it is provided with fenders, guards, mooring bitts, cleats and all other attachments necessary for convenient and successful opera- tion. It is approximately 100 feet long and 60 feet wide, and is divided | into six water-tight compartments by bulkheads extending full length and width. Four single barrel reversible ONGSIDE CRUISER WASHINGTON. © steam capstans made by the American Ship Windlass Co. are provided for maneuvering. It was specified that the crane must have a freeboard of not less than 34 feet when lifting the maximum load, and in addition must have a capacity in excess of these loads of 300 gross tons deck load, with a freeboard for the combined loads of not less than 2 feet, conditions which of course called for the most careful calculations on the part Of the engineers. The main frame is of structural steel and consists of two A frames, with bracing, supporting three inde- pendent trolley tracks each about 220 feet long, carried at a height of about 80 feet above the deck. Each canti-