1912.] Acetylmethylcarbinol and 2.3-Butylene Glycol. 77 



show for comparative purposes the result of the action of B. lactis aerogenes 

 on glucose and mannitol respectively. 



Table I. 





Glycerol. 



Glucose. 



Mannitol. 



1. 



2. 



3. 



4. 







35 



2 



37-7 



37-3 



17 



1 



32 



5 





6 



1 



5-0 



7-3 



5 



1 



2 



5 





13 







12 -7 



11 -13 



5 





8 



6 







05 



1 -6 



4-03 



2 



4 



3 



2 



2.3-Butylene glycol ... 



9 



9 



Not esti 



mated 



(27 



2) 



(12 



0) 





6 





4-9 



7-5 



1 







1 



5 





22 



4 



28 -37 



31 -8 



38 







35 



5 





110 



6 



144 -0 



160 -7 



198 



3 



180 



3 



Ho, c.o. per grm 



79 



8 



139 -0 



156 -7 



82 



4 



138 



3 



Eatio H 2 /C0 2 







72 



0-97 



0-97 







42 







77 



The figures in brackets are estimated from other experiments. 



Table II shows the number of carbon atoms per molecule of glycerol 

 decomposed, represented by each product. 



Table II. 





Glycerol. 



Glucose. 



Mannitol. 



1. 





3. 



4. 



5. 



2.3-Butylene glycol ... 

 Formic acid and C0 2 



Total 



Hydrogen, atoms per 

 molecule 



1-42 

 0-18 

 0-40 

 0-12 

 39 

 0-58 



1-43 

 0-15 



0-05 



Not esti 

 0-69 



1-49 

 0-22 

 0-34 

 0-12 

 mated 

 0-82 



1-34 

 0-31 

 0-33 



0- 15 

 (2 -17) 



1- 64 



2 -57 

 0-15 



52 

 0-20 



(0 -97) 



1 -53 



3-09 



2-71 



2-99 



5-94 



5-94 



0-65 



1.13 



1-28 



1 -33 





Columns 4 and 5 are again comparative ones of B. lactis aerogenes on glucose 

 and mannitol. 



It is interesting to find that alcohol accounts for 35 - 2 per cent, of the 

 glycerol used, as against 17"1 per cent, in the case of glucose. Harden 

 suggested (8) that the source of the alcohol might be the presence in the 

 molecule undergoing decomposition of the terminal group GH 2 (OH)-CH(OH)-. 

 This was confirmed in the case of glucose and mannitol, this latter substance 

 yielding twice the amount of alcohol produced under similar conditions from 



