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

266 DAVY S ELECTRO-CHEMICAL TELEGRAPH.
THE SIGNAL ALPHABET.
The keys, H 7, move the arm, A S, to the right, A T, to the left.
J7, "7 AS, " left, AT, " right.
" K 7, B S, " right, B T, " left.
M 7, B S, " left, B T, " right.
0" 7, " C S, " right, C T,' left.
" U7, " C GS, " left, C T,' right.
These are all the various deflections which it is possible to
give the six needles. Those, however, which deflect to the
right, not closing the circuit, produce no effect, and are of no
account. I will, therefore, omit them, and simply give the
table, thus:
The keys, H 7, move the arm A T, to the left. No. 1.
" JJ 7, A S, " 2.
(" K 7, " B T, " " 3.
" M 7, " B, " " 4.
L" 07, " CT, " " 5.
" UU 7, " C S, 6" 6.
Telegrcaphic Letters.
1, e e e e....
3 e #e o I e e 1 1
4 o o
A B C D E F G H I J K L Ml N 0 P Q R S T U V W X Y Z
The above represents the telegraphic characters marked upon
the prepared fabric. The spaces are numbered from the top.
The first six of the telegraphic letters require each a signal
wire, and the common wire D, with one battery.
The next six require each two signal wires, with two batteries, whose joint currents pass in the same direction on the
common wires D.
The next six require each two signal wires only, with two
batteries joined together, so as to form a compound battery;
the negative pole of one connected with the positive pole of the
other.
The next two require each three signal wires, with three
batteries, whose joint currents pass in the same direction along
the common wire D.
The next six require each three signal wires only, with three