Having described the instrument, its operation is as follows: At the transmitting station is the pole changer, such as we have described in figures [48], [49] and [50], and the magneto electric machine such as is described in figures [45], [46], and [47], and are properly connected, and in the circuit with the instrument of the receiving station, such as we have just described. For one single circuit, one wire extends from the transmitting to the receiving station, the return half of the circuit is the earth. Thus the current passes from the generator along the extended wire to the receiving station, and to the copper plate, then returns through the ground to the copper plate of the transmitting station, to the pole changer and the magneto electric machine. Thus the circuit is complete.
It is clear, from what has preceded, that when the pole changer is thrown to the left side, (the machine being in operation,) the fluid is made to pass in the direction of the arrows, shown at P and N. Then the N′ pole of the left hand magnet advances with its pen, K′, to the paper, E, and a dot is made, and the S′ pole of the right hand magnet recedes with its pen, H, from the paper, until the other end of the magnet strikes the stop, V′. Now, if the letter to be formed, requires two dots in succession from the same pen, the circuit is broken, and the fixed magnets, N and S, bring back the deflecting magnets, D′ and D′, to their former position, when the pole changer is again thrown to the left, and the magnets are deflected in the same manner as at first. Thus two dots are marked upon the paper, on the right hand line. But, now, let the pole changer be thrown to the right hand side, and the current is reversed. The N′ pole of the left hand magnet, with its pen, K, recedes from the paper until it strikes the stop, V, and the S pole of the right hand magnet, with its pen, H′, advances to the paper and makes its dot upon it on the left hand line. The pole changer is then instantly brought to the middle position, and the magnets resume their natural place, by the assistance of the stationary magnets, N and S. The sign which has been marked upon the paper during this operation is
· ·
·, and represents 9.
The following represents Mr. Steinheil’s telegraphic alphabet:
| · | ·· | · | ·· | ·· | ···· | · · | · | · | · | ||
| · · | · · | · | · | · | ···· | · · | ·· | ·· | |||
| A | B | D | E | F | G | H | CH | SCH | I | K | L |
| ··· | ·· | · · | ·· | · | · · | · · | ·· | ||||
| ··· | ·· | ·· | ·· | · | · | · · | ·· | ||||
| M | N | O | P | R | S | T | V | W | Z | ||
| ··· | · ·· | ·· · | ··· | · | · | · | · | ·· | |||
| · | · | · | · | ··· | · ·· | ·· · | ··· | · | ··· | ||
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | ||
Masson’s Electric Telegraph.
“In 1837, M. Masson, Professor of Philosophy at Caen, made trial of an electric telegraph, at the college of that city, for a distance of about 600 metres. He employed, for developing the galvanic current, an electro magnetic apparatus, similar, on the contrary, to that of Mr. Pixii, and made it act on magnetic needles placed at two ends of the circuit. Since that time, however, M. Masson has endeavoured to simplify and gradually improve his apparatus.”[33]
Davy’s Needle and Lamp Telegraph.
The following extracts from the London Mechanic’s Magazine, vol. 28, page 296 and 327, 1837, is all the description we are able to find in relation to it:
“There is a case, which may serve as a desk to use in writing down the intelligence conveyed; and in this, there is an aperture about sixteen inches long, and three or four wide, facing the eyes, perfectly dark. On this the signals appear as luminous letters, or combinations of letters, with a neatness and rapidity almost magical. The field of view is so confined, that the signals can be easily caught and copied down without the necessity even of turning the head. Attention, in the first instance, is called by three strokes on a little bell; the termination of each word is indicated by a single stroke. There is not the slightest difficulty in decyphering what is intended to be communicated.”
Extract from page 327.