BERMUDA DOCK. 305 



the vessel. At the time the side is lowered, the vessel, being 

 only half out of the water, has nearly the same stability as 

 when afloat, and any listing movement causes nearly the same 

 displacement, bringing into play nearly as much righting power 

 as if she were floating at her light water line. The sides of the 

 dock are successively lowered and again secured long before the 

 bilges of the vessel are raised out of the water, so that at 

 the moment when the vessel ceases to add stability to the dock 

 the stability is more than ample, being that due to the two sides 

 in combination. 



As already mentioned, this dock can readily dock itself on an 

 even keel, without being taken apart or removed from its inoor- 



FIG. 301. 



ings ; even the under side of the pontoon can be raised several 

 feet clear of the water for examination and cleaning. To do 

 this, the sides are lowered until the decks are level with the 

 pontoon ; they are then secured and pumped out, thus raising 

 the pontoon and the fixed corners well out of the water, as 

 shown in Fig. 301, leaving ample space for a boat or raft to 

 pass under. Similarly, when the sides have been secured in 



FIG. 302. 



their highest position, and the pontoon has been pumped out, 

 the bottom of the sides will be raised clear of the water, as 

 shown by Fig. 302. 



Bermuda Floating Dock. This dock is an example of the 

 round-bottom type, closed at either end by caissons, and has 

 the following dimensions : 



Feet. 



Length over all 381 



Length between caissons 330 



Breadth over all 124 



Breadth insido 84 



Depth over all ... 72 



X 



