4o 
Mr. Davy’s Lecture on some 
The coated glass plates of Beccaria strongly adhere to 
each other when oppositely charged, and retain their charges 
on being separated. This fact affords a distinct analogy to the 
subject ; different particles in combining must still be sup- 
posed to preserve their peculiar states of energy. 
In the present early stage of the investigation, it would be 
improper to place unbounded confidence in this hypothesis ; 
but it seems naturally to arise from the facts, and to coincide 
with the laws of affinity, so ably developed by modern 
chemists; and the general application of it may be easily 
made. 
Supposing two bodies, the particles of which are in different 
electrical states, and those states sufficiently exalted to give 
them an attractive force superior to the power of aggre- 
gation, a combination would take place which would be more 
or less intense according as the energies were more or less 
perfectly balanced ; and the change of properties would be 
correspondent^ proportional. 
This would be the simplest case of chemical union. But 
different substances have different degrees of the same elec- 
trical energy in relation to the same body : thus the different 
acids and alkalies are possessed of different energies with regard 
to the same metal ; sulphuric acid, for instance, is more power- 
ful with lead than muriatic acid, and solution of potash is more 
active with tin than solution of soda. Such bodies likewise 
may be in the same state or repellent with regard to each other, 
as apparently happens in the cases just mentioned; or they 
may be neutral ; or they may be in opposite or attracting states, 
which last seems to be the condition of sulphur and alkalies 
that have the same kind of energy with regard to metals. 
