378 



STUDIES ON FERMENTATION. 



The abscissae represent the time expressed in hours ; the or- 

 dinates, the degrees of temperature. The exterior temperature 

 was 0° C. (32° F.) ; the atmosphere was calm. The wort was 

 jDumped on to the coolers at 5.20 p.m., its temperature then 

 being 85° C. (185° F.), and the operation of pumping lasted 

 from 5,20 to 5.30 p.m. The first determination was made at 

 5.30 p.m., and was repeated every ten minutes until 7.30 p.m. 



sh^a 6 A- 7^ 



9 A iqA l\h j_2''l 



Fig. 84. 



2h. 



Curve of cooling of the wort on the coolers (December ISth, 1875). 



Between 7.30 and 8.30 p.m. it was repeated every twenty 

 minutes ; after that, it was repeated every half-hour until 

 2 a.m., when the wort went down to the fermenting vessels. 

 The mean depth of the wort was 8'5 centimetres (3'1 inches). 



Having determined the rate of cooling in the brewery, we 

 made the following experiment : a known quantity of wort 

 from the copper — deprived, consequently, of oxygen — in the 



[' The corresponding Fahrenheit degrees are, proceeding from 5'"30 

 downwards to 2'', 107% ISV, 100-4% 82-8°, 72% 64-4% 58-l% 53-1% 50% 

 47-7%— D. C. R.] 



I 



