284 Mr, G.S. Walpole. The Action of [Oct. 22, 
would contain nearly all the acetylmethylearbinol of the medium. 
A number of experiments were then made to determine the volume of 
distillate in each case which, when made up to 10 c.c. with distilled water 
and 1 cc. Fehling’s solution, just brought about complete reduction in 
10 minutes. This was found to be :— 
There was no other volatile reducing substance discovered in these 
fermentation products, nor was there any indication of a foreign substance 
which would vitiate, by its presence, the accuracy of these results. The 
amount of acetylmethylearbinol produced in the aérobic fermentation was 
therefore a = 5°6 times that produced in the similar fermentation under 
anaérobic conditions. 
The acetylmethylcarbinol was found to be levo-rotatory, but was not 
obtained pure enough for a determination of the [@]p. 
Experiments with synthetic acetylmethylearbinol (kindly made by 
Mrs. D. Norris) show that under the above conditions 1 cc. of Fehling’s 
solution is reduced by 2°48 mgrm. of the carbinol. The absolute quantities 
found were therefore approximately, 
mcrobic task! 2 tanec eee = 2°83 grm. 
Anaérobic flask ......... oe Uy Be 
The extraction of crude 2 : 3-butanediol (boiling point, 181 to 183°) from 
the two residues of the two cultures was performed in precisely the same 
manner in each case. In the anaérobic experiment 7:9 grm., and in the 
aérobic experiment 6°85 grm. were obtained. The values of [e|p in 
10-per-cent. solution in dry ether for these two samples were found to be 
+1:71 and +1°52 respectively. 
Experiment [1.—The culture made under anaérobic conditions did not 
grow. The stopper was therefore removed, the flask reinoculated and the 
stopper replaced, and the flask was then incubated. Growth then took place. 
After the expiration of three weeks both flasks were found to contain 
pure cultures of B. lactis aérogenes. The liquids were distilled exactly as 
described for Experiment I, and the reducing power to Fehling estimated. 
This was found to be, for 1 c.c. Fehling solution— 
Anaérobic flask ...... 22°4 c.c. approx. 
AGrobicuilask ee eeewes 3°6 5, 
