54 
ON PERCHROMIC ACID. 
ject of importance in commerce. Its flavour is delicious, and its intox- 
icating qualities equal to or surpassing those of alcohol. It is a strong, 
diffusible stimulant, similar to the hydrated ether, but more grateful 
to the taste." 
Several of our manufacturers now furnish chloroform of good quality, 
and we shall, ere long, have its powers fairly tested, as a strong interest 
js felt in reference to it by the medical public. W. P., Jr. 
ART. XV.— ON PERCHROMIC ACID. 
By M. Barreswill. 
On mixing a concentrated solution of chronriic acid with 
an equally concentrated solution of peroxide of hydrogen, 
a violent effervescence is immediately produced by an escape 
of pure oxygen ; when, on the contrary, the solutions are 
mixed in a very diluted state, the liquid assumes an intense 
blue colour. This blue colour is of extremely slight stabi- 
lity, and appears to point to the formation of a very readily 
decomposable higher oxide of chromium than chromic acid; 
and which, when concentrated solutions are employed, is 
decomposed immediately on its production. The blue com- 
pound may be obtained by mixing a dilute solution of peroxide 
of barium with an excess of muriatic acid in a dilute solution 
of bichromate of potash, but it is so unstable that it cannot 
be isolated from this liquid. It is, however, according to the 
following experiments, perchromic acid, Cr^ C . To de- 
termine the constituents of this body, the author made use 
of Gay-Lussac and Thenard's apparatus for the analysis of 
organic substances with chlorate of potash, substituting for 
the tube a balloon capable of holding half a pint of water. 
