The telegraph manual: a complete history and description of the semaphoric, electric and magnetic telegraphs of Europe, Asia, Africa, and America, ancient and modern.

SCIENCE OF THE VOLTAIC BATTERY. 81
the salt, materially increases the quantity of electricity set in
motion; but the pile will not in any sensible manner increase
the divergence of the gold leaves,-its intensity, therefore, is
not materially augmented.
The pile, represented by fig. 2, is connected at each end
with a wire; A B C is the frame to hold. the plates; s s are the
silver plates, and z z are zinc plates; i are the moistened
flannels, and i i the top and bottom end boards; p, the positive
pole, is connected with the wire at the top, and at the bottom
N, the negative, to the wire. This was the voltaic pile as
originally introduced by that distinguished philosopher Volta,
of Pavia, in the year 1800.
In order to increase the intensity of the voltaic or electric
current, it is necessary to increase the number of the plates;
and to develop the greater quantity current, it is attained by
the increase of the size of the plates. The centre of the battery
or column is neutral, but the ends are in opposite electrical
states; the zinc extremity negative, and the gold, silver, platinum or other metallic applications, positive.
TIIE SCIENCE OF THE VOLTAIC BATTERY.
The action of the voltaic pile gradually diminishes from the
time it is first put together, until at length the effect appears
to cease. This diminution of power is more rapid in proportion
to the energy given to the pile in the first instance by the
larger quantity of acid mixed with the water. To restore the
original energy, it is necessary to decompose the pile, to clean
the zinc and copper disks, and to moisten the cloths again.
Such an apparatus is therefore attended with much trouble.
To obviate it, Volta contrived another arrangement, which he
called d couronne de tasses. He connected a piece of zinc to a
piece of copper by soldering to them a short length of bent copper
wire. Having procured a number of such connected plates,
he put them into a row of glasses containing acidulated water,
taking care so to dispose them that the zinc and the copper
connected together should be in separate glasses, in the manner represented in figure 3.
To the copper plate in glass 1, a wire is attached to serve as
a conductor for forming connection. In the same glass there is
a zinc plate connected with the copper immersed in glass 2.
In this manner each glass contains a zinc and copper plate
connected by a wire, which are kept apart in the fluid, and the
series may be continued to any extent. By bringing the wire
attached to the first plate in connection with a similar wire
6