316 
MISCELLANY. 
When we make a mixture of lactic acid and concentrated sulphuric acid, 
the latter acid being in great excess, we obtain, by gently heating the 
vessel which contains it, an abundant disengagement of pure oxide of 
carbon. 
In reflecting on the relation of composition which exists between sugar 
and lactic acid, I was led to think that it was not impossible that a simi- 
lar action might be established if sugar was substituted for lactic acid in 
the foregoing mixture. 
The formula of crystallized cane sugar is C 24 H 22 11 j that of hy- 
drated lactic acid is represented by 
C 24 H 24 12. 
2 
thus, therefore, if the elements of 1 equivalent of water be substracted 
from the elements of 2 equivalents of lactic acid, we have the formula 
of crystallised cane sugar. 
Jf we admit, with M. Juerin Vary, that the formula of anhydrous 
sugar of starch is C 24 H 24 12 , it is evident that 2 atoms of lactic acid 
would just contain the elements of I atom of anhydrous sugar of fecula. 
I heated in a matrass 20 grammes of cane sugar with 80 grammes 
of concentrated sulphuric acid ; the mixture being maintained at a very 
gentle heat, a very brisk reaction was manifested, a very abundant 
disengagement of gas was produced, the mass swelled up, turned 
black, and became almost solid ; I then stopped the operation. I had 
collected about 2 quarts of gas. 
This gas formed, as was proved by the analysis which I made, 
of a mixture of carbonic acid and oxide of carbon. I ascertained that 
it contained about one-fifth of its volume of carbonic acid. I should 
say, moreover, that the composition of the mixture varies in each ope- 
ration. 
Deprived, by washing with lime water, of all its carbolic acid, this 
gas is colorless; it does not redden litmus; it is decomposed at a red 
heat of potassium, which absorbs its oxygen and produces a positive 
carbon ; it burns with a pure blue flame. I proved by eudiometrical 
analysis that it consisted solely of carbon. Sugar of starch and fecula 
furnished analogous results, as it is evident, the reaction of sulphuric 
acid on sugar or starch differs from that which the same acid exerts on 
lactic acid, inasmuch as, with the latter acid, the oxide of carbon is ob- 
tained without the mixture of carbonic acid, but the separation of the 
latter is so easy that it will always be more economical to employ sugar. 
This process, which is much more economical than all those which 
have ordinarily been used, is so easy of execution, that T have reason 
to hope that it will be adopted in all laboratories for the preparation of 
oxide of carbon. — Chem. from Journ. de Pharm. 
