meeting was divided into sections, we could not hear all, and sel 
those departments according with our own predilections,—physics au 
chemistry ; and we therefore confine our communications to facts bro 
out in these two sections. ‘ : 
The presidents of the section of chemistry were successively Li 
Wohler, Schénbein, and on the declinature of Bunsen, H. Rose. 
sessions began on the 17th of September. fee 
Schlossberger on the property of ammoniacal oxyd of copper disso 
ing cellulose—This property was made known some years since ] 
Schweitzer. Not only cellulose but also silk is soluble in this reagent. — 
e ammoniacal sulphate of copper acts as a solvent only from the exces 
of oxyd of copper present. Mr. Schlossberger finds that the solvent 
power increases with the proportion of copper, and that the hydrate 
the same effect. The precipitate shows no trace of organization oF 
tallization; and it does not appear to differ in percentage com 
from that of cellulose. : a 
These same alkaline salts do not precipitate the solution of sil ; a 
the fact may be made the basis of a process for separating silk from” 
The solution of cellulose is precipitated also by alcohol, a concen 
trated solution of honey, gum Arabic, or dextrine. The cupro@ 
niacal liquid has no action on pyroxyline or collodion. Inuline, age 
2. There 
the proportion is 3 grams in 100 grams of the calcareous pat 
but we have shown that there is hardly 0°05 in a kilogram. 
are: (a) potable waters; (b) vegetable substances,—although none TT “ 
tain so little that it is necessary to expe 
