160 Hature'0 Attracted. 



trolled by an electromagnet. Each time the 

 circuit was opened or closed the wheel would 

 move forward one step, and each step repre- 

 sented one of the letters of the alphabet, so 

 that the wheel, like the type-wheel of a print- 

 ing telegraph, had fourteen teeth, each tooth 

 representing two steps. As the reciprocating 

 movement of the escapement had a pallet or 

 check-piece on each side of the wheel, its 

 movement was arrested twenty-eight times in 

 each revolution. These twenty-eight steps cor- 

 respond to the twenty-six letters of the al- 

 phabet, a dot and a space. On the shaft of the 

 escape-wheel is fastened a hand or pointer, 

 which revolves over a dial-faee having the 

 twenty-six letters of the alphabet, also a dot 

 and space. The pointer was so adjusted that 

 when the escape-wheel was arrested by one of 

 the pallets it would stop over a letter, showing 

 thus, letter by letter, the message which the 

 sender was spelling out. 



The transmitter consisted of a crank with 

 a knob and a pointer on it, which was mounted 

 over a dial that was lettered in the same way 

 as the face of the receiving-instrument. A 

 revolution of this crank would break and close 

 the circuit twenty-eight times; that is to say, 

 there were fourteen breaks and fourteen 

 closes of the circuit. If now the transmitting- 

 pointer and the receiving-pointer are unified 

 so that they both start from the same point on 



