. Shipbuilding and Shipping Record. itating the occupants into thesea. With the Graham single ilavit and suspension gear, on theother hand, tlie lowering and releasing of the boat on an even keelis assured, even when the ship is down by head or stern. Wheneverthe boat is waterborne automatic release of the Imat is elTectedthrough the action of a single releasing liook aftei wards mechanical gear forming an integral part of the lirahamdavit is mounted upon it at a convenient working heightenclosed in a sheet metal easing. It consists brictly of a hand winchhaving fitted to it a se
. Shipbuilding and Shipping Record. itating the occupants into thesea. With the Graham single ilavit and suspension gear, on theother hand, tlie lowering and releasing of the boat on an even keelis assured, even when the ship is down by head or stern. Wheneverthe boat is waterborne automatic release of the Imat is elTectedthrough the action of a single releasing liook aftei wards mechanical gear forming an integral part of the lirahamdavit is mounted upon it at a convenient working heightenclosed in a sheet metal easing. It consists brictly of a hand winchhaving fitted to it a self-sustaining screw brake, which—should tlicmen at winch handles for any reason cease heaving—automaticallyand securely holds the load. Then- is also a mechanical slewingor turning gear which controls the davit at all points. It is con-nected to the hoisting shaft, thus enabling the one handle to hoistthe boat and turn the davit. The chain—or wire rope—whidi formsthe medium of suspension is double from the pulley in head of. ALAht or D£Cff S^enii^O POSITION or Sf^UGS^ Diagram showing Mechanical Gear o£ GrEiham Davit. davit and is led through a single sheave Ijloek whic-li carries thedisengaging hook, but is single from the head of davit and led downthrough roller-guides in the interior of davit, stowing itself in tiiehoUow bottom end of davit, and in this way securing freedom fromhamper and confusion around the boat station, not infrequentlythe cause of mishap. By means of the winch two men can lift a30-ft. boat oS the chocks, swing her outboard, and lower her to thewater in from 45 to .50 seconds for the wliole operation. Tlielowering is under the control of one man, as com[)ared with the twomen necessary with the ordinary davits. The time taken to lift,swing outboard, and lower a 30-ft. boat with the ordinary davitsis about 4 minutes, while 12 men are necessary to accomplish theswinging out, and 4 men the lowering. By means of the mechanicalslewing gear the Graham d
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