ate. The best method of removing the
charge I have found to be, to cover the finger with a single fold of a silk
handkerchief, and breathing on the stem, to wipe it immediately after with
the finger; the ball B and its connected wire, &c. being at the same time
_uninsulated_: the wiping place of the silk must not be changed; it then
becomes sufficiently damp not to excite the stem, and is yet dry enough to
leave it in a clean and excellent insulating condition. If the air be
dusty, it will be found that a single charge of the apparatus will bring on
an electric state of the outside of the stem, in consequence of the
carrying power of the particles of dust; whereas in the morning, and in a
room which has been left quiet, several experiments can be made in
succession without the stem assuming the least degree of charge.

1204. Experiments should not be made by candle or lamp light except with
much care, for flames have great and yet unsteady powers of affecting and
dissipating electrical charges.

1205. As a final observation on the state of the apparatus, they should
retain their charges well and uniformly, and alike for both, and at the
same time allow of a perfect and instantaneous discharge, giving afterwards
no charge to the carrier ball, whatever part of the ball B it may be
applied to (1218.).

1206. With respect to the balance electrometer, all the precautions that
need be mentioned, are, that the carrier ball is to be preserved during the
first part of an experiment in its electrified state, the loss of
electricity which would follow upon its discharge being avoided; and that
in introducing it into the electrometer through the hole in the glass plate
above, care should be taken that it do not touch, or even come near to, the
edge of the glass.

1207. When the whole charge in one apparatus is divided between the two,
the gradual fall, apparently from dissipation, in the apparatus which has
_received_ the half charge is greater than in the one _originally_ charged.
This is due to a peculiar effect to be described hereafter (1250. 1251.),
the interfering influence of which may be avoided to a great extent by
going through the steps of the process regularly and quickly; therefore,
after the original charge has been measured, in app. i. for instance, i.
and ii. are to be symmetrically joined by their balls B, the carrier
touching one of these balls at the same time; it is first to be removed,
and then the apparatus