126 Mr. Gr. F. C. Searle : A Method of Determining 



its way back to the boiler. At the top of the cylinder the 

 surplus steam passes out by a small escape pipe. A copper 

 tube^ 2 mm. in internal diameter,, is coiled four times round 

 the end Y and is soldered to the rod ; this tube serves to 

 convey the cooling water. 



The temperatures o£ the water before and after passing 

 through the coiled tube are ascertained by means of the 

 thermometers D and C, which are fixed into the small brass 



Fig. 1. 



JUL 



vessels H and G by indiarubber stoppers. Water enters H 

 by the tube P and leaves G by the tube Q, the necessary 

 connexions being completed by the indiarubber joints I, I. 

 A convenient way of obtaining a steady flow of water is to 

 allow the inflow pipe attached to P to dip like a siphon into 

 a reservoir in which the water is kept just overflowing by a 

 stream from a tap. By changing the difference of level 

 between the surface of the water in the reservoir and the 



