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cross-seel ion C-D and E-F. A piece of the pipe by which the milk 

 or cream is elevated from the 

 pasteurizing heater is cut and 

 the larger pipe (a) is substi- 

 tuted, so that the milk comes 

 from the heater at (b) and 

 leaves at (c). In this way the 

 warm milk in rising surrounds 

 the copper tube (d) ; this tube 

 contains a mixture of ether and 

 glycerin; the former floating on 

 top being evaporated by the heat 

 from the milk and the pressure 

 thus created (which is correla- 

 tive to the temperature of the 

 milk) acts on glycerin and, (Fj g . 31) 



through this, on the rubber diaphragm (g) and the piston (p). 

 From this piston the pressure is carried through the lever (q) 

 to the spiral spring in the compartment (h). This spring may be 

 loosened or tightened by the wheel (i) and thus the resistance of 

 the piston (p) against the ether pressure may be regulated. 



The lower part (r) of the piston (p) forms a valve which, 

 when the piston is pressed down, shuts off the steam which enters 

 at (o) and leaves for the heater at (m). In order that the reg- 

 ulator shall not weigh down the steam pipe a pipe support is 

 screwed into the lower part (k). When the rubber diaphragm 

 has to be renewed (which Mr. Casse claims is only a few times a 

 year) the piece (e) is removed, allowing the ether and glycerin 

 to run out, the old rubber diaphragm (g) is removed and the 

 piston (p) taken out and wiped off. The valve is cleaned and the 

 piston replaced, the new diaphragm put in and the piece (e) is 

 held with the opening up (f, Fig. 2) so that it may be filled first 

 with a small quantity of pure glycerin and then with ether. The 

 opening (f) is closed with a small cork so as to hold the ether 

 and glycerin, while the piece (e) is replaced and bolted. When 

 the regulator is heated up the bolts should be tightened, if neces- 

 sary. As soon as the ether expands the little cork is forced out 

 and the glycerin runs out and presses on the diaphragm. 



It must be observed that it is necessary, to insure good work, 

 that the copper tube (d) is cleaned every day and kept free from 

 the inevitable film of dried on milk. To do this is easy as the 

 elevating pipe (a) may be removed by loosening the union (1). 



