em to
permeate and pass through them, whether separately or in their neutral
state of reciprocal combination.

But it is probable, that imperfect conductors may possess more or less
of either the vitreous or resinous ether combined with them, since
their natural atmospheres are dissimilar as mentioned below; and that
this makes them more or less imperfect conductors.

6. Those bodies which are perfect conductors, have probably neutral
electric atmospheres gravitating round them consisting of an equal or
saturated mixture of the two electric ethers, whereas the atmospheres
round the nonconducting bodies probably consist of an unequal mixture
of the electric ethers, as more of the vitreous one round glass, and
more of the resinous one round resin; and, it is probable, that these
mixed atmospheres, which surround imperfect conducting bodies, consist
also of different proportions of the vitreous and resinous ethers,
according to their being more or less perfect conductors. These minute
degrees of the difference of these electric atmospheres are evinced by
Mr. Bennet's Doubler of Electricity, as shown in his work, and are
termed by him Adhesive Electric Atmospheres, to distinguish them from
those accumulated by art; thus the natural adhesive electricity of
silver is more of the vitreous kind compared with that of zinc, which
consists of a greater proportion of the resinous; that is, in his
language, silver is positive and zinc negative. This experiment I have
successfully repeated with Mr. Bennet's Doubler along with Mr.
Swanwick.

7. Great accumulation or condensation of the separate electric ethers
attract each other so strongly, that they will break a passage through
nonconducting bodies, as through a plate of glass, or of air, and will
rend bodies which are less perfect conductors, and give out light and
heat like the explosion of a train of gunpowder; whence, when a strong
electric shock is passed through a quire of paper, a bur, or elevation
of the sheets, is seen on both sides of it occasioned by the
explosion. Whence trees and stone walls are burst by lightning, and
wires are fused, and inflammable bodies burnt, by the heat given out
along with the flash of light, which cannot be explained by the
mechanic theory.

8. When artificial or natural accumulations of these separate ethers
are very minute in quantity or intensity, they pass slowly and with
difficulty from one body to another, and require the best conduc