LAUNCHING DATA FOR A BATTLESHIP. 103 



Maximum width of sliding ways 56 ins. 



Effective width of sliding ways 55 ins. 



Bearing area 4,110 sq. ft. 



Material of sliding ways Yellow pine 



Length over which poppets distributed pivoting pressure Plate 39 



Number of wedges, spaced, port, 465; starboard, 447. 



Total number of wedges 912 



Wedges, oak, about 7 ft. by 6 ins. tapered 11/16 in. per foot. 



Length of forward poppet, about 17 ft. 



Length in contact with ways, before launch, about 10 ft. 6 ins. 



Total weight on ground ways, tons 1 1,942 



Initial pressure per sq. ft., tons 2.91 



Calculated buoyancy at pivoting, tons 8,636 



Pressure on fore poppets at pivoting, tons 2,850 



Pressure per square foot under fore poppet at pivoting, tons 28.2 



Draught, after launching, with cradle, forward 10 ft. 9 ins. 



Draught, after launching, with cradle, aft 16 ft. 6 ins. 



Depth of water over way ends 9 ft. 10 ins. 



Travel before rudder of vessel entered water, about 103 ft. 



Distance traveled when cradle entered water, about 172 ft. 3 ins. 



Distance from A. P. to after end of ways 215 ft. 3 ins. 



Distance traveled when stern began to lift 545 ft. 



Maximum speed, per second 23.7 ft. 



The vessel was finally held by hard pine sole pieces 56 feet X 5 feet, 280 square inches 

 sectional area, on each side, with the addition of two dog shores per side of 14 feet X 14 

 feet yellow pine. After the dog shores were removed the sole pieces were sawn through for 

 about 112 square inches of sectional area when the vessel tore away without aid from the 

 50-ton hydraulic jacks provided in case of any sluggishness in starting. 



It is considered advisable by the Fore River Shipbuliding Corporation to check the run 

 of vessels after they are water-borne and clear of ways, and, in the case of the Nevada, this 

 was accomplished by the usual method of wooden masks at stern and anchor chains and 

 manila rope stoppers alongside the vessel of which there were 200 of 9-inch manila. 



The most interesting difference between the launching arrangements of the two vessels 

 is in the forward poppet. In place of somewhat elaborate rocker used on the Oklahoma we 

 curved or cambered the forward end of fore poppet cribbing for about 6 feet 6 inches of its 

 total length of 17 feet to give a clearance of 6 feet at the forward end, which equals a rock- 

 ing radius of about 42 feet 6 inches as compared with 50 feet radius of the Oklahoma. Be- 

 tween the rocker and top of sliding ways we introduced white pine 3 inches thick to act as 

 cushion or crushing chocks and distribute any excessive pressure when the stern begins to 

 lift. Unfortunately, we were unable to recover these crushing chocks in a condition that 

 would permit of a true determination of their value for purposes intended. 



The Chairman : — You have heard Mr. Tawresey's interesting paper, and have seen 

 the reproduction of the photographs taken by moving-picture of the launching of the Okla- 



