ccumulated ether.

Thus by alternately replacing this loose coating, and withdrawing it
from the sealed charged jar, by means of an insulating handle; and by
applying it to one insulated conductor, when it is in the vicinity of
the jar; and to another insulated conductor, when it is withdrawn;
vitreous electric ether may be accumulated on one of them, and
resinous on the other; and thus I suspect an immense quantity of both
ethers may be produced without friction or much labour, if a large
electric battery was so contrived; and that it might be applied to
many mechanical purposes, where other explosions are now used, as in
the place of steam engines, or to rend rocks, or timber, or destroy
invading armies!

The principle of this mode of accumulating the two electric ethers in
some measure resembles that of Volta's Electrophorus and Bennet's
Doubler.

VI. _Accumulation of electric ethers by heat and by decomposition._

When glass or amber is heated by the fire in a dry season, I suspect
that it becomes in some degree electric; as either of the electric
ethers which is combined with them may have its combination with those
materials loosened by the application of heat; and that on this
account they may more forcibly attract the opposite one from the air
in their vicinity.

It has long been known, that a siliceous stone called the tourmalin,
when its surfaces are polished, if it be laid down before the fire,
will become electrified with vitreous, or what is called positive
electricity on its upper surface; and resinous, or what is called
negative electricity on its under surface; which I suppose lay in
contact with somewhat which supported it near the fire.

In this experiment I suppose the tourmalin to be naturally combined
with resinous electric ether like glass; which on one side next
towards the fire by the increase of its attractive power, owing to the
heat having loosened its combination with the earth of the stone, more
strongly attracts vitreous electric ether from the atmosphere; which
now stands on its surface: and then as the lower surface of the stone
lies in contact with the hearth, the less quantity of vitreous ether
is there repelled by the greater quantity of it on the upper surface;
while the resinous ether is attracted by it: and the stone is thus
charged like a coated jar with vitreous electric ether condensed on
one side of it, and resinous on the other.

So cats, as they lie by the fire in a