282 Mr. G. 8. Walpole. The Action of [ Oct. 22, 
Found. | Calculated C,H;0:. 
ae \ 
(Cpe eens 526 53°33 | 
Ns reas: 11-07 ea | 
\ 
It will be seen that the combustions of the “ glycol” prepared from the 
diphenylurethane consistently give figures for the carbon content which are 
less than the theoretical. This cannot be put down to errors in the com- 
bustion process. It is suggested that a small percentage (about 1 per cent.) 
of water persistently accompanies the glycol even in its distillation. A 
sample treated in aqueous solution with bromine in the light gave diacetyl 
from which the osazone of melting point 241° to 243° was prepared. The 
identity of this osazone with the corresponding one from the “ crude glycol” 
was established. With iodine and potash an aqueous solution of the glycol 
gives an immediate precipitate of iodoform. 
It is seen that the “crude glycol” has given large quantities of a pure 
diphenylurethane from which a pure butanediol has been prepared by alkaline 
hydrolysis. This recovered diol yields diacetyl on oxidation, and this shows 
conclusively that the butanediol has a straight chain with the two hydroxyl 
groups in the 2: 3-position. On this, and the fact of the large yield of 
diphenylurethane melting at 199°5 when phenylisocyanate acts on the 
“crude glycol” is based the conclusion that well over 90 per cent. of the 
“erude glycol” consists of an inactive 2:3-butanediol. From the remaining 
10 per cent. only one substance has been definitely isolated and this appears 
also to be an inactive 2: 3-butanediol, but yields a phenylurethane melting 
at 157°. It is probable that one of these inactive diols is the 7. or dl. 
isomer and the other the internally compensated isomer, but no attempt has 
been made to decide this question. 
Il. THe Errect oF FREE OXYGEN ON THE ACTION OF Bb. lactis aérogenes 
ON GLUCOSE AND ON 2: 3—BUTANEDIOL. 
In the experiments described the amount of acetylmethylcarbinol 
obtained from 50 grm. of glucose was very small and it was desired to 
increase the yield of this substance. An endeavour to do this by passing 
oxygen into the inoculated flask during incubation proved successful. It 
was also found that acetylmethylearbinol is abundantly formed when the 
bacillus is cultivated in a solution of the butanediol in 1 per cent. peptone 
water in a current of oxygen. The oxidation of an alcohol group to 
a ketone group by an organism in an abundant supply of oxygen is 
