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Brown. — Some Studies on Yeast . 
flasks, one of which is shown at F ; 1 these were of about 225 c.c. capacity, 
and were fitted in such a manner that the gas-delivery tube did not extend 
below the rubber stopper, in order that at the final operation the flasks could 
be completely filled with the wort, which was also driven round the bend E. 
Some of the de-aerated wort was then withdrawn from the large flask, 
and was fully saturated with air by strong agitation, the temperature being 
noted. A measured quantity of this fully aerated wort, along with a weighed 
amount of freshly cultivated and pressed yeast, generally amounting to 
o*2 grm., was transferred to one of the small flasks F, which was then rapidly 
and completely filled up with de-aerated wort through the tube D. The pinch- 
cock G was then closed and the rubber connexion severed just behind it. 
In this manner a series of flasks was obtained containing known pro- 
portions of fully aerated and de-aerated wort'with definite amounts of yeast. 
A complete series consisted of nine such flasks ranging from fully aerated 
1 Before inserting the plug of F the supply tube B, G, d must be completely filled with the de- 
aerated wort. 
