114 Scientific Intelligence. 
ification as to obtain a useful residue, and not a product of no value, 
ture, by combining the sulphuric acid with alumina, so as to obtaina 
residue of some commercial value. 
lumine does not saponify directly; byt M. Cambacéres overcomes 
this difficulty, by availing himself of the property, which some alkaline 
alumine ; and as the solution goes on, the alkali separates from the fatty 
body with which it was combined. ‘The aluminous soap thus formed, 
is then precipitated by the aid of an excess of alkali, a large quantity of 
water, or a saline solution. The soap separates in a gelatinous mass, 
and its decomposition is effected without difficulty by means of the acid. 
The silica of the clay separates from the alumine when thé saline solv: 
tion is concentrated in order to obtain the salt in a solid state. 
M. Favre. By operating on large quantities of this secretion, M. Favre 
has detected a new acid, having the constitution of creatine, sarcosine, 
4 
etc., which he calls hydrotic acid. The subject from whom he pro- 
cured the material for examination was a philanthropic physician, Dr. 
ecker, who voluntarily exposed himself to a high temperature, and 
thus furnished M. Favre 40 litres of sweat. 
Researches on the presence of boracic acid in mineral waters.—MM. 
Baup, Bouis, Filhol, Bechamp of Strasburg have in turn recognized 
On the composition of the air confined in vegetable mould.—M. 
Boussingault, in this paper gives an account of numerous experiments 
