HENRY AND THE TELEGRAPH. 301 



later, and forms tLe earliest publication of the actual operation of the 

 "Morse telegraph."* The dispatch is as follows: 



r 



215—3 6—2—5 8 — 



112—0 4 — 01 8 3 7 



This cipher is thus explained by the writer, reference being had to a 

 dictionary suitably prepared with numbered words. "To illustrate by 

 the diagram, the word 'successful' is first found in the dictionary, and 

 its telegraphic number, '215,' is set up in a species of type prepared for 

 the purpose; and so of the other words. The type then operate upon 

 the machinery and serve to regulate the times and intervals of the pas- 

 sage of electricity. Each passage of the fluid causes a pencil at the ex- 

 tremity of the wire to mark the points as in the diagram. To read the 

 marks, count the points at the bottom of each line. It will be perceived 

 that two points come first, separated by a short interval from the next 

 point. Set '2' beneath it. Then comes one point, likewise separated by 

 a short interval. Set '1' beneath it. Then come five points. Set '5' 

 beneath them. But the next interval in this case is a long interval; con- 

 sequently the three numbers comprise the whole number '215.' So pro- 

 ceed with the rest until the numbers are all set down. Then by referring 

 to the telegraphic dictionary, the words corresponding to the numbers 

 are found, and the communication read. Thus it will be seen that by 

 means of the changes upon ten characters, all words can be transmit- 

 ted."! 



In the above line or diagram representing the telegraphic dispatch, 

 the symbol "A" (or inverted V), which occurs twice in the lower line, 

 represents a cipher or zero ; and this character, when preceding a figure 

 or group of figures, indicates that the figure or group is to be read as an 

 actual number, and not as the index of a word. Counting thus the num- 

 ber of V points in the above dispatch forming groups separated by a 

 line ( — ),we obtain the following numbers : "215 — 36 — 2 — 58 — 112 — 01 

 — 01837." And this message when translated by help of the numbered 

 dictionary will read " Successful ex])eriment with telegraph September 

 4 1837." 



An account of this success, published in Silliman's Journal for Octo- 

 ber, added the statement: "Since the 4th of September, one thousand 

 feet more of wire No. 23 have been added, malciug in all two thousand 



*NotwithstaiKling the very crude condition of this invention in Sei)tember, 1;^37, as 

 compared with that of Schilling in 1830 (or probably in 18<j:5), and that of Gauss in 

 1833, the fact that intelligible signals were actually exhil)ited by it at this date, fully 

 :usti1ies the acceptance of this period as the 1 ime of its reduction to practical operation. 



tNew York Journal of Commerce, Thursday, September 7, 1837: (on the editorial 

 page.) 



