. How to make and use electricity ... e knob of the closes the circuit, and the electric current instantly fillsthe wire from B to Y. It magnetizes A; A draws down thelever B, and presses the point of a style on a strip of paper, C, that is drawn over a roller. The operator ceases to pressupon the key, the circuit is broken, and instantly B is raisedfrom the paper by a spiral spring, D. Let the operator pressupon the key only for an instant, .or long enough to countone, a simple dot or indentation will be made in the if he presses upon the key long enough to count threethe poi
. How to make and use electricity ... e knob of the closes the circuit, and the electric current instantly fillsthe wire from B to Y. It magnetizes A; A draws down thelever B, and presses the point of a style on a strip of paper, C, that is drawn over a roller. The operator ceases to pressupon the key, the circuit is broken, and instantly B is raisedfrom the paper by a spiral spring, D. Let the operator pressupon the key only for an instant, .or long enough to countone, a simple dot or indentation will be made in the if he presses upon the key long enough to count threethe point of the style will remain in contact with the paper thesame length of time, and as the paper is drawn along beneaththe point a short, straight line is produced. This short line is called a dash. These dots and dashes con-stitute the alphabet of telegraphy, and this is the style of re-ceiving by means of paper. If the strip of paper be removed and the style is allowed tostrike the metallic roller, a sharp click is heard. Again, when. the lens is drawn up by the spiral spring it strikes a screwpoint above, and another tick or click, differing slightly insound from the first, is heard. A listener is able to distinguishdots from dashes by the length of the intervals of time thatelapse between these two sounds. Operators generally read by ear, giving heed to the clickingsounds produced by the strokes of a little hammer. A receiverso used is called a sounder, a common form of which can beseen represented in Figure 6. In larger lines, where the current must travel miles of wire,a relay, which throws the circuit of the sounder on alocal battery, is used. Otherwise the sounder would giveeither a very feeble or no sound at all. The following is the alphabet and figures: 52 HOW TO MAKE AND ABCDEF GHI J KLMNOP Q R S T U V W X Y Z & , ? 12 3 4 5 6 7 8 9 0 CHAPTER X. * CONCLUSION. In 1850 the practicability of conveying an insulated wire un-der water was proved by the laying of a single co
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectelectricity, bookyear
