442 Essay towards a natural 
from the non-metallic bodies. Those which originally had served 
as the basis for this distinction can no longer be used as such, 
since most of the metals hitherto re egarded as of that class are 
brittle ; and because some liave been discovered even lighter than 
water; and iode, and even carbon, when its particles are very 
close, as in animal charcoal, present the metallic lustre and a 
perfect opacity; and because chemists have discovered in carbon 
the property of being a conductor of the electric fluid, &e. A 
more important character, viz. that of producing s: alifiable bases 
on being united with oxygen, cannot be considered as sufficient 
for characterizing exclusively the metals; because some metals 
do not form any, because the boric and the nitrous acids are com~ 
bined with the sulphuric acid, and because the products of those 
conibinations have a!l the characters of the acid salts, which 
they resemble even more by their easy crystallization than se- 
veral metallic solutions the oxide of which is precipitated in pro- 
portion as they are evaporated; solutions which are only consi- 
dered as salts, precisely because they are compounded of an acid 
and of the oxide of a body which we have been accustomed to 
regard as a metal. ‘This character, which is admitted besides 
as exclusive, will remove tellurium from arsenic, and particularly 
from iode; whereas the far more important property which it 
possesses of forming with hydrogen a permanent acid gas places 
it necessarily between those two bodies. The first object to 
which I shall turn my attention in the following article, will be 
to examine to what extent we might preserve the distinction of 
the metals, and of the non-metallic bodies, by subjecting the 
character which we shall choose for defining it in a precise man- 
ner, to the modification required by the necessity of rendering it 
conform to the natural order’ of simple bodies. I shall confine 
myself to remarking, that in the way in which it has been ad- 
mitted, it has retarded the progress of the true theory of che- 
mistry, by inducing a neglect of the observation of the properties 
by which certain metals are connected with the other simple 
bodies, and to which we cannot pay too much attention, when it 
is required to ascertain the truly natural order which exists be- 
tween both the one and the other. The character drawn from 
the various degrees of affinity has still more contributed to esta- 
blish between bodies, and particularly between the metals, ap- 
proximations disavowed by nature. I shall confine myself to 
quoting in this respect, an example which appears to me very. 
striking. Silver and gold form equally with oxygen combina~ 
tions which an clevated temperature easily decomposes: from 
that instance those two metals have been regarded as being en- 
titled to be placed very near each other in every methodical ar- 
rangement of siinple bodies, Nevertheless the degree of ne 
or 
— Sw 
