BUOYANCY AND STABILITY OF TROOP TRANSPORTS. 149 



Table II. — Results of Combined Inclining and Rolling Experiments. 



The America, during the experiment, was near her light condition, although 

 she had 4,300 tons of coal and 1,450 tons of water on board. The Mount Vernon 

 was on about the same draught as she would be carrying troops across the Atlantic, 

 when on her eastbound voyage and nearing a European port ; she had 4,650 tons of 

 coal and 2,570 tons of water on board. The Covington was fully equipped, but, 

 like the two other ships, without troops or cargo. 



2. Various Conditions of Loading. — A careful investigation was made of the 

 probable loading of the ships under various conditions, and the corresponding 

 draught and trim were calculated. In particular, the following conditions were 

 studied : — 



( 1 ) When a transport sails from the port of embarkation, fully equipped, with 

 troops and cargo on board. 



(2) When she arrives at the port of debarkation. 



(3) When she sails from that port. 



(4) When she returns to the port of embarkation. 



For each of these conditions the position of the center of gravity and the meta- 

 centric height were calculated, or, where no inclining experiment was available, the 

 position of the center of gravity was determined by an approximate calculation. 



3. The Period of Roll at Sea. — In all cases, whether an inclining experiment 

 was made or not, the period of roll was observed later when at sea in the various 

 conditions of loading. As far as possible the observations were taken under cir- 

 cumstances when the rolling was of a fairly regular character and small or moder- 

 ate in amplitude. By comparison with other ships of similar size and t3^pe for 

 which K was known, this coefficient was estimated for each vessel and the meta- 

 centric height calculated approximately from the formula: — 



GM^ 



K'B' 



It is also possible in a general way to judge of the stability of a ship directly 

 from the observed period by comparing it with that of other similar ships. This 



