This constituted the completed invention of the telegraph, and on comparing the work of Profs. Henry and Morse, it is only fair to say that Prof. Henry’s contribution to the telegraph is still in active use, while the Morse register has been practically abandoned, as no expert telegrapher requires the visible evidence of the code, but all rely now entirely upon the sound click of the electro-magnet placed in the local circuit and known as a sounder, the varying time lengths of gaps between the clicks serving every purpose of rapid and intelligent communication. The invention of the telegraph has been claimed for Steinheil, of Munich, and also for Cooke and Wheatstone, in England, but few will deny that it is to Prof. Morse’s indefatigable energy and inventive skill, with the preliminary work of Prof. Henry, that the world to-day owes its great gift of the electric telegraph, and with this gift the world’s great nervous forces have been brought into an intimate and sensitive sympathy. [Illustration: FIG. 8.--PERFECTED MORSE REGISTER.] Whenever an invention receives the advertisement of public approval and commercial exploitation, the development of that invention along various lines follows rapidly, and so when practical telegraphic communication was solved by Henry, Morse, and others, further advances in various directions were made. Efforts to increase the rapidity in sending messages soon grew into practical success, and in 1848 _Bain’s Chemical Telegraph_ was brought out. (U. S. Pats. No. 5,957, Dec. 5, 1848, and No. 6,328, April 17, 1849.) This employed perforated strips of paper to effect automatic transmission by contact made through the perforations in place of the key, while a chemically prepared paper at the opposite end of the line was discolored by the electric impulses to form the record. This was the pioneer of the automatic system which by later improvements is able to send over a thousand words a minute. [Illustration: FIG. 9.--HOUSE PRINTING TELEGRAPH.] [Illustration: FIG. 10.--STOCK BROKER’S “TICKER,” WITH GLASS COVER REMOVED.]