CHAPTER XVIII 



The sealing tank may be on the ground floor if the apparatus is high enough, 

 otherwise it has to be located in a pit. A pump is employed to raise the 

 water from the sealing tank. 



FIG. 196 



(c) Each cell is supplied with an individual pump. In this case the water 

 from a cell may pass into a receiver connected with the vapour calandria of 

 the one next in series. This receiver is known as a " flash pot/' and has for 

 its object the release and utilization of the vapour corresponding to the differ- 

 ence in pressure between the two calandrias. 



