464 TRAKSACTIOKS OF THE 



The regular subject, " Telegraphs," being called for, the chairman urged 

 their importance. 



Mr. Seelcy. — In long lines it is necessary to have relay machinery. The 

 batteries which generate the current by which signals are given are at the 

 ends of the lines, but when the currents are not powerful enough, we have 

 relays at local stations. It is very important to dispense with these battery 

 relays, and I have no doubt there can be a machine made so delicate as to 

 take their place. 



Dr. Vanderweyde. — Common electricity was tried in the days of Dr. 

 Franklin. It is, however, unmanageable when compared with electro- 

 magnetism. Shortly after the time of Volta, a telegraph was constructed 

 by filling 24 tubes with water and making each one when required a part 

 of the circuit ; bubbles of hydrogen appearing at the end indicated the 

 letter, and so words were spelled out. This was of course a very slow pro- 

 cess. The Needle telegraph was invented 20 years afterwards. Oersted 

 observed the vibrations of the needle in 1820. In the needle telegraph, the 

 needle was caused to vibrate, and in doing so to strike a bell. The essen- 

 tial feature of Morse's telegraph is the horseshoe magnet. It had been 

 discovered in 1825, that a horseshoe of soft iron, surrounded by a helix, 

 was converted into a magnet while a current of electricity was passing 

 through the helix, and lost its magnetism as soon as the current ceased. 

 The combination of a horse shoe and a helix, conducting wires, and voltaic 

 batteries, constitute the essential parts of Morse's telegraph. 



Chairman. — What connection has the name of Prof. Ampere with the 

 telegraph ? 



Dr. Vanderweyde. — Ampere discovered that a current would not only 

 magnetize, but that two currents would either attract or repel each other. 



Dr. Reuben could corroborate the remarks of Dr. Vanderweyde. The 

 invention of the telegraph was widely different from ordinary inventions. 

 It was in advance of the regular development of the science of electricity 

 and there was a reason why it should come to maturity when it did. An 

 intense desire for rapid commuRication of thought was felt, which, as soon 

 as electricity was discovered, led men to seek the agency of this mysterious 

 and fleet messenger to convey our errands from place to place. The first 

 invention that we have any direct account of, is that of Dr. Watson, in 

 1747. Over the chimneys in London, for a distance of two miles, he car- 

 ried currents of common electricity. This shows that the idea of telegraph- 

 ing had been in men's minds — that it is old. After various important dis- 

 coveries, we come at last to the electro-magnetic telegraph. Sturgeon, in 

 1825, made the first electro-magnet. Professor Henry increased the power 

 of the electro-magnet, and rendered a very feeble current of electricity 

 available for telegraphing. In 1830, Professor Morse devised his mode of 

 recording, which he completed in 1844: 1837 was emphatically the tele- 

 graphing age. Now, notwithstanding the many and brilliant discoveries of 

 others. Prof. Morse deserved very great honor, for he introduced a very 

 superior method of recording. 



