STUDIES ON FERMENTATION, 367 



and the formula (2) given in the preceding section. At the 

 temperature of 5° C. (41° F.), at which the above worts were 

 " gathered,"* and not taking into account the very small cor- 

 rection that should be made for the difference of half a degree 

 on Balling, we find, by this formula, as the ratio of the 

 coefficients of the solubility of oxygen in saturated wort and in 

 water — 



c 



- = 0-82 

 c 



Now, at the temperature of 5° 0., the quantity of oxygen 

 held in solution in 1 litre of water is, according to Bunsen, 

 0'036 litre, at the atmospheric pressure, and therefore at the 

 pressure of yth atmosphere, which is that of the oxygen in 

 atmospheric air, it will be — 



— F — litre =: 7'2 c.c. — [that is, 2 cubic inches per gallon.] 



And, consequently, in the case of saturated wort, it will be — 



7'2 c.c. X 0'82 = 5'904 c.c. — [that is, 1"62 cub. inches per gall.] 



Multiplying this last number of c.c. by the different degrees 

 of saturation found, we shall obtain the volumes of oxygen held 

 in solution in 1 litre of different worts : — 



r Unfiltered 0-500 x 5-904 c.c. = 2-952 c.c. 

 Summer worts | j,.^^^^^^ ^^.g^^ ^ ^.^^^ ^^ ^ 4..23 ^^ 



^^ f Unfiltered 0-850 x 5-904 „ = 5-018 „ 



Winter worts [^-^^.^^^^ 0950 x 5-904 „ = 5-609 „ 



It is important to notice that we are here dealing with wort 

 taken from the fermenting vessel just before it was pitched ; 



* [For non-teclinical readers we may explain the expressions 

 •' gathered," here used, and " turning out," used on page 365. " Turn- 

 ing out " describes the operation of emptj'ing the cupper contents into 

 the hop-back, or the Jwp-iack contents on to the coohrs. "Gathering" 

 refers to the time when the worts are finally intermixed and tveigJud, 

 prior to the commencement of vinous fermentation. — F. F.] 



