STUDIES ON FERMEXTATICN. 363 



other hand, at the same temperature of 11° C. (51"8° F.). 

 The following fio-ures were obtained for the ratios of solu- 

 bility : — 



6. From the preceding results it is easy to deduce a 

 general formula which shall give the coefficient of solubility 

 of oxygen in any wort, marking B° by Balling, and at tem- 

 perature t°. 



From the figures of (2) it follows that aboTe and below the 

 temperature of 15° C. (59° F.), the ratio which the coefficient 

 of solubility of oxygen in water bears to that of the solubility 

 of the same gas in wort varies about O'OOG for each degree of 

 the thermometer. From the figures of (3) it follows that the 

 same ratio varies about 0'002 for each degree of Balling above 

 and below the 15th degree on the instrument. 



By taking c for the coefficient of solubility of oxygen in 

 water at f C, and c for that of oxygen in wort also at f C, 

 and having a density B, by Balling at 15° C. ; and taking X 



for the ratio -at 15° C. and 15° Balling, we shall have 



-, = X + (B-15) 0-022-(/-15) 0-006. 

 c 



By carefully ascertaining the ratio - for different worts, and. 



c 



c 



adopting the preceding formula, we have found, for X a mean 

 value of 1-16. 



* [The Balling saccharometer being almost unknown in England, we 

 may explain that its indications are for percentages of sugar in saccharine 

 solutions, or of extract in worts ; 17"9° Balling, therefore, means 17'9 per 

 cent, of sugar or extract in the respective liquids. — P. F.] 



