WILLIAM SIEMENS, F.K.S. II 



cooling the water. The refrigerator may be placed conveniently 

 on the back of the tender. 



The application of the regenerative condenser to low-pressure 

 engines, as shown in Fig. 2, Plate 1, requires but a short notice 

 after what has been said already ; the letters refer to the same 

 parts as in the former description of the high-pressure condenser 

 shown in Fig. 1. In the low-pressure condenser the steam at the 

 time when it is released from the cylinder has not sufficient force 

 to expel the air and heated water from- the condenser into the 

 atmosphere, and a partially vacuous space must be provided for 

 their reception. For this purpose the side B of the displacing 

 cylinder, which in the arrangement hitherto described is always 

 empty, is put in communication with the exhaust valve G of the 

 condenser, and receives the charge of water and air at the time 

 when the piston C is at the opposite end ; a second valve is 

 provided, through which the water is expelled into the hot well F 

 during the return of the piston C. For the convenience of 

 arrangement, the displacing cylinder is reversed in this case. 



The chief advantages obtained by the application of this con- 

 denser to the low-pressure engine are : 



1. The requisite amount of injection water is reduced in the 

 proportion of 3 to 1. 



2. The feed water of the boiler is obtained nearly boiling hot, 



which constitutes a saving in fuel of = about 10 per 



960 



cent. 



3. The whole amount of heat generated under the boiler is 

 given off by the engine in the form of water at 210 Fahr., which 

 in most cases may be advantageously employed for heating build- 

 ings, washing, dyeing, and other purposes. 



4. A large proportion of the power required for working the air 

 pump is saved. 



The author proposes to conclude this paper with a short historic 

 sketch of the steam engine condenser, to illustrate the distinct 

 features of this regenerative system. 



In Newcomen's engine the condensation of the steam was 

 effected by the alternate introduction of a jet of cold water into 

 the steam cylinder itself. The cold water naturally cooled the 

 walls of the cylinder, which in their turn condensed a large portion 



