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

BAKEWELL'S ELECTRIC COPYING TELEGRAPH.
CHAPTER XXI.
Manipulation of the Electric Copying Telegraph of F. C. Bakewell of EnglandThe Apparatus Described-Secrecy of Correspondence, its Advantages and
Disadvantages.
MANIPULATION OF THE COPYING TELEGRAPH.
THERE have been many plans proposed for transmitting intelligence by electricity, and producing, at a given destination,
a fac-simile of the writing presented at the sending station.
The following seems to be the most practicable yet devised, and
the inventor, Mr. F. C. Bakewell, of England, is confident that
it will accomplish the great desideratum on lines of any
length.
The copying telegraph transmits copies of the handwriting
of correspondents. The advantages of this mode of transmission
are, that the communications may be authenticated by the
recognized signatures of the parties by whom they are sent.
and as the writing received is traced from the original message,
there can be no errors of transmission; for every letter and
mark made with the pen is transferred exactly to the other
instrument, however distant.
The electro-chemical mode of marking the paper, invented
by Mr. Davy, is adopted in the copying process. The writing
is copied on paper soaked in a solution of prussiate of potash
and muriatic acid, a piece of steel wire serving for the pen.
The paper is placed round a cylinder about six inches in diameter, and a steel wire, connected with the copper end of the
voltaic battery, presses upon it, and is carried slowly along by
a screw as the cylinder revolves. By this arrangement, when
the voltaic current passes uninterruptedly from the wire through
the paper to the cylinder which is connected with the zinc end
of the battery, lines are drawn upon it at the same distance
apart as the threads of the screw that carry the point. These
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