218 THE PROPELLING MACHINERY OF THE U. S. S. LEVIATHAN. 



bilges, so that the oil drain pipes to the drain tanks are visible. There is also plenty 

 of clear space to allow access to the drain connections under the barrels of the tur- 

 bine casings. 



The wing turbine compartments extend clear across the full width of the vessel 

 and are about 80 feet in length. 



No regular platform or floor is arranged in these engine-rooms, but at the same 

 level as the floor of the forward engine-room, gratings extend right round the out- 

 board sides of the turbines. 



Access to the turbine rotor bearings and thrusts is provided for by means of 

 ladders. 



The air pumps and line shaft bearings of the inboard shafts are also reached 

 by means of a ladder and passageway, arranged beside the entrance door to the aft 

 engine-rooms, and on the starboard side this passageway permits of access to the 

 main dynamo compartments. 



Under the regular full-speed-ahead steaming conditions the steam from all the 

 boilers is admitted to the high-pressure ahead turbine, out of which it passes over to 

 the mid-pressure, and from the exhaust end of this unit it is divided and passes into 

 the two low-pressure ahead turbines, and from these to the four main condensers. 



For go-astern conditions the boiler steam is admitted to each of the high-pres- 

 sure astern units, from which it passes over to the low-pressure astern turbines, 

 thence to the main condensers, that is, the port high-pressure astern exhausts to the 

 port low-pressure astern, and the starboard high-pressure astern to the starboard 

 low-pressure astern. 



Under maneuvering conditions, such as when entering or leaving port, the two 

 ahead turbines driving the two port shafts and the two ahead turbines of the star- 

 board shafts are operated independently, in which case the mid-pressure turbine 

 takes boiler steam directly. 



There are four main condensers of Weir's "Uniflux" design, which have a 

 total cooling surface of 68,700 square feet, two being placed back to back in each aft 

 engine-room, on the inboard side of the low-pressure ahead turbines. 



The tubes are %-inch diameter external, and the length between the tube sheets 

 is approximately 8 feet 9 inches, whilst the circulating sea water makes two passes. 



The exhaust nozzles to each condenser are fitted with two hydraulically op- 

 erated gate valves about 39 inches wide by 90 inches high, so that any defective 

 condenser can be shut off. 



The centrifugal pumps, each pair being driven by one compound reciprocating 

 engine, supply the cold sea water to the two condensers of each engine-room. The 

 discharge pipes from each pump are about 39 inches diameter, and in addition, a 

 cross-connection pipe is also fitted between the pump discharge pipes of each engine- 

 room. 



Directly under the condensers there are two single-acting air pumps of Weir's 

 "Dual" type in each engine-room, which discharge to the hot well tanks. 



Eight Weir's type of "Simplex" double-acting feed pumps draw water from the 



