ELECTRICITY.
*55
dissolve while others will grow upon the other terminal.
The same thing can be done still better by filling the
horizontal tank for the vertical attachment with the
solution of lead acetate, and then bending a piece of
platinum wire or of tin wire around the interior of the
tank. Then, on inserting another wire at the centre of
the solution, and making connection with two or three
cells so as to make the centre wire the negative and the
hoop the positive pole, a beautiful growth of metallic
crystals will shoot out from the centre and spread out
over the entire field. In place of the solution of lead
use a strong solution of the bichloride of tin, using a
tin hoop in the solution. Crystals of tin will shoot out
and appear in great beauty.
These solutions in the horizontal tank should not be
more than an eighth of an inch deep.
HEATING BY THE CURRENT.
Make a small coil of platinum wire, and thrust the
ends of the wire through the rubber of the tank, as
Fig. 112.
shown in the engraving, Fig. 112. Fill the tank with
water, and having projected the whole, send the current