AMERICAN INSTITUTE. 465 



Prof. Mason said tl.at Professor Morse's experiments were tried in his 

 room in the New York University, in 1837. He had a mile of wire expe- 

 rimenting with. 



Mr. Stetson. — Professor Morse made a telegraph practicable, and there- 

 fore he deserves great honor. 



Chairman. — John Stewart Milne said that Oersted and Ampere dis- 

 covered the scientific truths upon which the telegraph is based. To Morse, 

 then, is due the honor of rendering these truths useful to us in. the business 

 of life. 



Mr. Stetson. — I wish to call attention to three points in connection with 

 the present condition of telegraphing, viz : the distance practicable, rapidity 

 of transmission and recording, and economy. These three seem of most 

 importance for our discussion, for we have little to do with the past except 

 as matter of curious history. I have some matters of improvement in 

 telegraphing now under examination which I cannot explain. I may, 

 however, say that they relate to telegraphing to great distances even when 

 the current becomes very feeble. To increase the effect when the current 

 has become feeble relays have been used, because currents of sufficient in- 

 tensity to be felt at a distance would melt the wires at the beginning of the 

 circuit. The power of the wire to conduct without melting, fixes the limit 

 of the intensity of the current. One way of overcoming the difficulty pre- 

 sented by weak batteries, is to employ relay magnets — that is, a weak bat- 

 tery attached to a magnet at a station along the line. Mr. Field told ua 

 that on landing, he received the shocks through the Atlantic cable upon 

 his tongue. Now I think that telegraphing by receiving the shocks upon 

 the tongue, is the most readily perceived with weak currents. The Baines, 

 or chemical telegraph, is the next in sensitiveness. In this a sensitized 

 paper is drawn between two metallic slips connected with the wires of the 

 circuit, as the current passes it produces a chemical change in the paper, 

 giving a kind of dirty stain, but when the electricity is stopped no stain is 

 produced. The length of the stain then constitutes the letter. This tele- 

 graph is entirely independent of the magnet. The length of mark is pro- 

 duced by the forward motion of the paper, which is moved by clock work 

 at a fixed speed. In every thing relating to the chemistry of the telegraph, 

 France is ahead of every other country, as this country is ahead of all 

 others in the mechanical part. If we can receive by the tongue, or record 

 by chemical action, there is no doubt but the rapidity of the telegraph can 

 be greatly increased. There are between Philadelphia and this city seven 

 wires, perhaps nine, and if we can only get greater rapidity of recording, 

 we may be able to do the same work with one. 



Chairman. — Have you met with any signals for sentences ? 



Mr. Stetson, — They are quite common. On the Erie R. R., there is an 

 elaborate system of directions printed and numbered, and to give any 

 directions, however complex, a number is all that need be telegraphed. 

 For instance, 27 — "send a train eastward," or, 38, "send one westward," 

 so as not to run out of time. There arc but few contractions, however, 



[Am. Inst. J 30 



