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

INJECTION OF POLES WITH SULPHATE OF COPPER. 693
Fig, 2,
n
A
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prepared. The sulphate is raised into the reservoir by means
of a pump or bucket. A lead or copper pipe passes from the
reservoir to another similar pipe placed horizontally. The
length of the latter pipe is proportional to the number of posts
to be injected, say one hundred feet for one hundred posts.
From this latter pipe branch out gutta-percha pipes terminated
by a copper or wooden faucet, by which the liquid is introduced
into the posts.
The posts to be injected, P P P, are all placed parallel, and in
a direction perpendicular to the main pipe, the tip-ends rest
upon the earth, on the border of the little gutter or trough into
which the liquid is to pass away. The butt or bottom ends of
the posts rest upon a beam raised a little over three feet above
the ground, in order to enable the workmen to put on the caps
or receivers conveniently. In order to cap the posts, there is
placed upon the upper face, or butt end, after the slice is sawed
off, to allow an early absorption, a piece of plank made from