J. Locke on the Electro-Chronograph. 231 





Art. XVIII. — On the Electro-Chronograph; by the inventor, 



John Locke. 



1. I propose first to give some brief definitions of the Electro- 

 chronograph, and secondly to correct some erroneous opinions 

 which have been formed, and some distorted and faulty publica- 

 tions which have been made, with reference to the invention. 



2. A very brief though defective definition of the chrono- 

 graph was suggested by the enquiry of a laboring man of this 

 place. Sir, said he, is it true that you are making a clock which 

 will make marks on paper a thousand miles off? This definition 

 is true affirmatively as far as it goes. But the sort of marks and 

 the use that can be made of them are essential points in the sub- 

 ject. It will mark down, at a distance, measured units of time 

 representing truly duration by space. This again falls short of 

 an account of the performance. It marks time in such a man- 



circuit. 



yf the finger 



yf any event in any other part of ti 

 nt. and that too with the facility of 



3. It is this last item, the manner of the marking, which has 

 been overlooked, and being overlooked has caused learned men and 

 learned bodies of philosophers to pronounce other inventions, as 

 Wheatstone's and Bain's interruptors, or break-circuits, so far as 

 electrical interruption is concerned, to be the equivalents of my 

 own, when really those interruptors could not begin to perform 

 their part of the functions of the electro-chronograph. Introduce 

 either Mr. Wheatstone's or Mr. Bain's interruptor into my chrono- 

 graph instead of my own and not a single observation could be 

 recorded with it. Prof. Wheatstone and others had special objects 

 in view, and they made excellent inventions to attain those ob- 

 jects. They accomplished what they proposed and I have a high 

 opinion of their merit. But when my own countrymen attribute 

 to them that which they never sought to accomplish, and to 

 which they have no claim, it is evident, even in the most charita- 

 ble view, that they did not understand the subject which they 

 nave been so ready to hand over to foreigners. 



4. I will now attempt to point out the peculiarity by which I 

 nave made it possible to record the exact time of events (astro- 

 nomical phenomena) at a distant station by means of a single 

 electrical circuit. The marks are made telegraphically on the dis- 



pape 



M, 



paper, stops the marKing wnemt 

 irhich traces a groove in the pape 



Bain 



