Biography of Berzelius. 11 
stances, particularly the power of crystallizing or of cohering in 
any form, in consequence of which compounds could separate 
from a solution, as precipitates or crystals; or else owing to the 
expansion taking place on passing into the gaseous state, by 
which they removed themselves from the sphere of action of 
solid or fluid bodies. The most important law established by 
Berthollet was, however, that of the so-called chemical mass, ac- 
cording to which the deficiency of a body in chemical affinity 
may be replaced or .compensated for by increasing its quantity: 
and it is indisputable that this law, although it has latterly been 
more and more forgotten, is perfectly correct. 
The first of these principles, established by Berthollet, viz: 
that all chemical combinations are possible between a certain 
maximum and minimum, and in indefinite proportions, was im- 
mediately disputed by Proust, who endeavored, by means of 
many ingenious experiments, to shew that every chemical com- 
bination takes place in definite proportions, and that between it 
and the nearest allied combination there is a certain interval 
within which there is no intermediate stage. 
Berthollet’s views were at that time apparently supported by 
the numerous erroneous representations of the composition of the 
most important compounds. Likewise the experiments which 
he made, or caused to be instituted, in order to disprove the as- 
sertions of Proust were far from being adequate. Proust’s exper- 
led him to enter upon this gigantic investigation. After the dis- 
covery of oxygen in the alkalies, the conjecture that all saline 
bases, and consequently ammonia, contained this element, was 
not unnatural. This view received a still greater probability by 
the discovery of the ammoniacal amalgam. 
Berzelius now commenced a series of investigations for the 
of chlorids, found the quantity of acid in the salt, and by the 
oss the quantity of oxygen in the base itself. 
On subjecting ammonia to the same process he was not able 
either to isolate the ammoniacal metal, or to combine it with the 
Mercury in such a quantity as to obtain a result. £ i 
