PULSATIONS PRODUCE WRITTEN CHARACTERS. 



be according to what has been already explained (129), by the 

 pendulum of a clock at any station, the motion of the anchor of the 

 escapement established at any other station to which the current is 

 transmitted, will be synchronous with that of the pendulum of the 

 clock which governs the pulsations of the current, and thus a 

 regular motion may be imparted by one clock to another, provided 

 that between them there be established a conductor, and the pen- 

 dulum of the one clock regulates the pulsations of the current, 

 which govern the movement of the anchor of the escapement of 

 the other. 



153. If the extremity of the lever, og, fig. 58, carry a pencil, 

 which presses upon paper, when the lever is drawn towards the 

 electro-magnet, and if at the same time the paper is moved under 

 the pencil with an uniform motion, a line will be traced upon the 

 paper by the pencil, the length of which will be proportionate to 

 that of the interval during which the lever off is held in contact 

 with the stop P. Now as the agent at s can regulate this interval 

 at will, by controlling the flow of the electric current, making 

 that current act for a short interval if he desire to make a short 

 line upon the paper, for a long interval if he desire to make a 

 long line, and for an instant if he desire to make merely a dot, it 

 will be understood how he can at will mark a sheet of paper at s", 

 500 miles distant, with any desired succession of lines of various 

 lengths or of dots, and how he may combine these in any way he 

 may find suitable to his purpose. 



We have here supposed the pencil attached to the end of the lever 

 to be alternately pressed against the paper, and withdrawn from it 

 by the motion of the lever. If, however, the paper be so placed 

 that the lever shall oscillate parallel to it, the pencil presented 

 to the paper will remain permanently in contact with it, and will 

 trace upon the paper a line alternately right and left, whose 

 length will be equal to the play of the end g of the lever, to which 

 the pencil is attached. If while this takes place the paper be 

 moved under the pencil in a direction at right angles to the line 

 of its play, the pencil will trace upon the paper a zigzag line, the 

 form of which will depend on the relation between the motion of 

 the paper and that of the pencil. When the current is in this 

 case suspended, the paper being moved under the pencil at rest, 

 a straight line will be traced upon it. 



Thus the paper will be marked either with a zigzag line, 

 or a straight line according as the current is transmitted or 

 suspended. 



If the current be alternately transmitted and suspended during 

 intervals of unequal length, at the will of the agent, at s, the 

 paper at s" will be marked by a line alternately zigzag and 



203 



