The Electrified Cotton
Take a small lock of cotton, extended in every direction as much as
can conveniently be done, and by a linen thread about five or six
inches long, or by a thread drawn out of the same cotton, tie it to
the end of the prime conductor; then set the machine in motion, and
the lock of cotton, on being electrified, will immediately swell, by
repelling its filaments from one another, and will stretch itself
towards the neare
t conductor. In this situation let the cylinder be
kept in motion, and present the end of your finger, or the knob of a
wire, towards the lock of cotton, which will then immediately move
towards the finger, and endeavour to touch it; but take with the
other hand a pointed needle, and present its point towards the cotton,
a little above the end of the finger, and the cotton will be observed
immediately to shrink upwards, and move towards the prime conductor.
Remove the needle, and the cotton will come again towards the finger.
Present the needle, and the cotton will shrink again.