250 Olservations and Experiments concerning’ 
4 
driven off from the points, so small in quantity as not to 
have appreciable gravity, as some have asserted; for the 
smell and taste are the same, whatever be the substance 
from which they issue. Lastly, 1 would know what is it 
which diffuses itself-from one conductor over the surface of 
znother, when separated by a great space; which in fine 
affects the organs of sensation with every effect of materi- 
ality. 
It is pretty certainly known that caloric enters into che- 
mical combination with bodies; and that it is a really che- 
mical combination is proved by the mutual change of pro- 
perties consequent on the union. Thus ice combining 
with free caloric forms water; the ice has lost its solidity, 
the caloric is become insensible. Are we to suppose that 
caloric is in a state differently electrical from that of water? 
The powerlul attraction must be all on the side of the ea- 
lorie, as water is said to be neutral with regard to other 
bodies. . . 
The hypothesis gives. no satisfaction concerning the se- 
paration of oxygen from various bodies by light. Is this 
substance also possessed of electric energy ? 
It is scarcely possible to conceive how the firm com- 
binations with which we are acquainted, can be occasioned 
by so weak an attraction as that of electricity 5. and the less 
so when it is considered how very small is the quantity of 
this power apparent in these very experiments which gave 
origin to the hvpothesis of electro-chemical attraction. 
The contact of very Jarge surfaces almost always requires 
to be made several times before the gold leaves of Bennett’s 
electrometer are sensibly affected. Every one is acquainted 
with the amazing sensibility of this instrament. What 
must be the effect of a single contact of one pair of atoms? 
Yet it is certain that.the attraction of one pair of atoms is 
of as great intensity as the combined powers of all, however 
great the quantity. The difficulty is considerably increased, 
if we suppose that the electricities of heterogencous bodies - 
exist im an absolute state. ‘They must then be so feeble as 
not to be appreciable by the most delicate instruments in 
our possession ; beside that, in the latter case, the agency of 
electricity must be entirely supposititious. The following 
experiment of Mr. Davy’s, I think, tends to confirm my 
objections against the efficiency of electric agency. 
Mr. Davy heated together a plate of copper and a plate 
of sulphur. The electricity which was scarcely sensible at 
56°, even to a condenser, became only powerful enough 
at 100° to cause a divergenee of the gold leaves without 
con- 
