APPENDIX. 931 



1692. Magnetic Telegraph Apparatus. 



Siemens and Halske, Berlin. 



The transmitter may be any dial instruments in which the currents are 

 generated by magnets. The receiving instrument prints upon a paper riband 

 from a double type wheel, at the same time indicating on a dial the letters 

 sent. The type wheel is of vulcanized caoutchouc instead of metal. 



1693. Two Automatic Cylinder Transmitters and print- 

 ing instruments working Duplex, i.e., so arranged that messages 

 may be transmitted from both stations simultaneously. 



Siemens and Halske, Berlin. 



The transmitter is an automatic finger key instrument, in which the letters 

 to be transmitted are formed in Morse code upon a cylinder of wires, these 

 wires being pushed forward by levers connected with the finger keys, so that 

 by depressing the keys corresponding to the letter to be sent, the complete 

 Morse signal is formed in the wires, which afterwards are brought by revolu- 

 tion of the cylinder into contact with levers connected to the battery and 

 line. 



1694. Automatic Type-printer, including transmitter, re- 

 ceiving instrument, and relays. Siemens and ffalske, Berlin. 



The transmitter is an automatic finger key instrument, in which the currents 

 to be transmitted are controlled by a cylinder of wires, these wires being 

 pushed forward by levers connected with the finger keys, so that by depressing 

 the key corresponding to the letter to be sent the necessary combination is 

 formed in the wires, which afterwards are brought by revolution of the cylinder 

 into contact with levers connected to the battery and line, and by this means 

 the numbers of currents requisite to bring the type wheel of the receiving 

 instrument to the desired letter are sent into the line. The relay consists of 

 a double armature of aluminium bobbins wound with silk covered wire, which 

 are drawn into or expelled from an intense magnetic field, according to the 

 direction of the current received in the coils from the transmitting instrument, 

 the bobbins causing contact to be made by their movement. The receiving 

 instrument has a double type wheel worked by an escapement, which is 

 actuated by two electro-magnets brought into play by the currents received 

 from the relay. 



1694:6. Charge and Discharge Keys (new form). 



t Warden, Muirhead, and Clark. 



1708a. Automatic Printing Telegraph, constructed by 

 C. H. Gr. Olsen, Christiania. 



C. H. G. Olsen, Optician, Christiania. 



This apparatus consists of two principal parts. 



1. The punching apparatus, on which the messages are prepared thus: 

 By depressing one of the keys of a keyboard in the apparatus, holes will be 

 punched in a paper ribbon, corresponding to letters and signs marked on the 

 keys. Then this ribbon is rolled up and applied in 



2. The printing apparatus, where it is % run over a metallic roller. When- 

 ever a hole appears, a steel pin will make contact with the roller and 

 send a current to the line. The current will liberate the armature of a magnet, 

 by which a wheel with engraved signs and letters will revolve, and another 

 paper ribbon, applied under this wheel, is lifted into contact with it. If 



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