, 1881-07-13

poses, such as lighting, heating, working
sewing machines, so that no interruption
of action would be produced by a temper
airy interruption of the electric supply
given by any main engine from which it
was derived.
Sir William Thomson reminds US that
the storage of force to be AFTERWARDS put to
practical uses is a very old contrivance, OF
which we may see an illustration IN the
winding of q watch and also that the
storage oil electricity has long been fami-
liar to men of science as q theoretical
possibility. There is often q long step,
however, from theoretical possibility 10
practical achievements ; aud what we are
now called upon TO notice is no longer that
such u storage may perhaps be accomplish
ed at s0me future time, but that il has
actually been accomplished upon what
may almost be called a working scale.
Many philosophers are of opinion hat
electricity, at no distant date, viii! entir ly
supeFssde fires TOR cooking and heating,
steam as a motor, and gas and oil ds
ilIuminants but hitherto it has been felt
as q great difficulty, economical rather than
scientific, that the agents proposed to
be superseded were themselves actually
employed to produce the electricity. 1t
has been asserted, moreover, that the
sectional area Of the metallic conductors
required to deliver electricity in quantities
suited 10 the requirements Ut town com
muUili-s would have to be enormously
large, and in q corresponding degree costly,
and that difficulties with regard to insula'
V;.0 ,.n,ll 10 "
But electricity is to be obtained from the
atmosphere by simple mechanical means
wherever any kind of motor power is
available; and, if it can be stored In
portable batteries and carried about tor
use, there seems to be no reason why it
should not be obtained in very cheap ways,
as by wind or water mills, by mechani-
cal contrivances for utilizing the ebb and
flow vi the tides, or by other applications
OF the power which nature everywhere
otf-rs for the use OF man, and which is so
frequently suffered to run to waste.
Neither Z. T. l R. 81 nor Sir William
Thomson has as yet furnished US with even
an approximate estimate OF the cost OF
maintaining a Faure'S battery us measured
by the amount OF force which it is capable
OF e~xcrting /; ard it must not be forgotten
that a million foot pounds, although sound
ing like an enormou amount to those
who are unfamiliar with the form of
expression, is yet something which would
not go very far In the WY OF supplying
the motor wants OF q workshop. Faure's
battery is constructed mainly of lead-a
circumstance which necessarily renders it
heavy, aud in a corresponding degree
costly of carriage while u new demand
for the metal, it in large quantities, must,
of course, tend to q co ns;derable enhance
ment of its price. Against these consider
ations must be set the obvious one that
other materials may be found capable of
employment in a similar manner; the
principle Of the battery being that the
electricity with which it is said to be
charged ia expended within it in the pro-
duction of chemical change, and is releas-
ed again by the establishment of q new
action by which the materials employed
are suffered to return to their original
condition. There is no primd tacie reason
why lead shoald be more available for this
kind of composition and decomposition
than some other substances; and, now
that the method Of producing the desired
effect has been made known in the case of
lead, philosophers will soon be engaged
10 the endeavour to discover som
substance which may offer still greater
l.. kL- rvOnn ITnI1o