triple Sulphuret, of Lead, Antimony, and Copper , &c. 47 
into a substance, I shall give the name of accidental integrant 
molecules. 
The effects of the last mentioned attraction, which is much 
weaker and much more variable than any of the others, seem 
to depend, in a great measure, upon the different circumstances 
in which the substances happen to be, at the moment of their 
formation. The new substance resulting from it, is not per- 
fectly homogeneous in all its parts, and, of course, ceases to be 
a chemical compound, properly so called. Every thing seems to 
show, that the introduction of these accidental molecules into 
the abovementioned substances, is governed by a particular 
law of attraction ; which acts in an uniform manner, so long as 
the formation of the substances under its influence takes place 
in the same circumstances ; but which varies, when those cir- 
cumstances happen to undergo any variation. Thus, for instance, 
in those kinds of tremolite that have the dolomite for matrix, 
(as in that from St. Gothard,) the carbonate of lime is in the 
proportion of but, in those kinds which have an argil- 
laceous matrix, it is only in the proportion of yj-. Thus also, 
the magnesian carbonate of lime, the chemical nature of which, 
as is shown by its form, is the same as that of pure carbonate 
of lime, admits, in consequence of the heterogeneous attraction of 
aggregation, the magnesian earth as a simple integrant part, and 
in proportions which vary, according to the circumstances in 
which the formation of this carbonate takes place. The magnesian 
carbonate of lime of Tyrol, for example, contains, according to 
* Assisted by the analysis of Mr. Chenevix, I think I have proved what I have 
here asserted ; and also, that the phosphorescence of the tremolite, which had been 
considered as one of the characters of that substance, is owing only to the particles of 
dolomite that are mixed with it. See Journal des Mines, No. 73. 
