BAINS CHEMICAL TELEGRAPH. 



sent along a thousand miles of wire, at the rate of nearly 20000 

 words an hour. 



We shall now explain the means by which this extraordinary 

 feat is accomplished. The despatch must pass through the fol- 

 lowing preparatory process : 



A narrow ribbon of paper is wound on a roller, and placed on 

 an axis on which it is capable of turning so as to be regularly 

 unrolled. This ribbon of paper is passed between rollers under a 

 small punch, which striking upon it makes a small hole at its 

 centre. This punch is worked by a simple mechanism so rapidly, 

 that when it is allowed to operate without interruption on the 

 paper passing before it, the holes it produces are so close together 

 as to leave no unperforated space between them, and thus is 

 produced a continuous perforated line. Means, however, are pro- 

 vided by which the agent who superintends the process, can, by a 

 touch of the finger, suspend the action of the punch on the paper, 

 so as to allow a longer interval to elapse between its successive 

 strokes upon the paper. In this manner a succession of holes are 

 perforated in the ribbon of paper, separated by unperforated 

 spaces. The manipulator, by allowing the action of the punch ;to 

 continue uninterrupted for two or more successive strokes, can 

 make a linear perforation of greater or less length on the ribbon, 

 and by suspending the action of the punch these linear perforations 

 may be separated by unperforated spaces. 



Thus it is evident, that being provided with a preparatory 

 apparatus of this kind, an expert agent will be able to produce on 

 the ribbon of paper as it unrolls, a series of perforated dots and 

 lines, and that these dots and lines may be made to correspond 

 with those of the telegraphic alphabet already described. 



Let us imagine, then, the agent at the station of departure pre- 

 paring to despatch a message. Preparatory to doing so, it will 

 be necessary to inscribe it in the perforated telegraphic characters 

 on the ribbon of paper just described. 



He places, for this purpose, before him the message in ordinary 

 writing, and he transfers it to the ribbon in perforated characters 

 by means of the punching apparatus. By practice he is enabled 

 to execute this in less time than would be requisite for an expert 

 compositor to set it up in common printing type. 



The punching apparatus for inscribing in perforated characters 

 the dispatches on ribbons of paper is so arranged, that several 

 agents may simultaneously write in this manner different mes- 

 sages, so that the celerity with which the messages are inscribed 

 on the perforated paper may be rendered commensurate with 

 the rapidity of their transmission by merely multiplying the 

 inscribing agents. 



E2 51 



