64 ON THE COMPOSITION OF STEARIC CACID. 
I have to add to this proof a new one, in the behaviour of 
stearic acid towards the sulphuric and chromic acids: if it be — 
heated after the addition of a little water, the mixture becomes 
green, owing to the oxide of chromium formed, and a part of the 
stearic acid is found changed into margaric acid. 
The new acid thus obtained melts at from 64° to 65°C. (147° to 
149° F.); however, it can be obtained by crystallizing from al- 
cohol, from which the stearic acid first separates, having a melt- 
ing point of from 59° to 60° C. (138° to 140° F.), which therefore 
agrees with that of margaric acid. 
