MOSES GERRISH FARMER. 417 



From 1864 to 1868 he experimented much with thermo-electric 

 devices, and discovered an alloy to be used for such a battery that had 

 much higher efficiency than any others which had been employed, — 

 one that compared favorably with the best we now have, except that it 

 is rather too brittle for commercial use. With such a source, however, 

 he coated steel and iron wire with copper for the sake of combining 

 high conductivity with great tensile strength, and this was developed 

 into a commercial enterprise of considerable magnitude. It was aban- 

 doned for some years, but its superior qualities for telephonic work 

 have again made demand for it. 



It appears that the first written description of what is now known 

 as the self-exciting dynamo, in which the dynamo current is sent 

 through its own field coils to strengthen its magnetism, was by 

 Mr. Farmer in a letter to an eminent English electrician. The same 

 idea occurred to several others about the same time, notably Siemens 

 and Varley, but its immense importance did not so impress any of 

 them as to put the idea into a practical form, and it remained for others 

 unknown before in the electrical field to put it into the commercial 

 shape so familiar now. 



In 1872 he was appointed Professor of Electrical Science at the 

 Torpedo Station at Newport, Rhode Island, a position which was quite 

 to his taste, and where he remained for nine years. 



During the first fifty years of his life he was in a constant struggle 

 with poverty and sickness. Like Agassiz, he had no time to make 

 money. He was so fertile in new things, he cared but little for the 

 worth of his inventions; though he took out many patents, he profited 

 little from them. His .work was mostly of a fundamental sort, and 

 few persons who have applied for patents on electrical devices for the 

 past twenty years have not found that Farmer had preceded them 

 in their territory, and there were few who had new ideas on any elec- 

 trical matter who could not find in some of his numerous note-books 

 the identical things already specified, and oftentimes the experimental 

 work done, but not published, for he does not appear to have written 

 much. 



Mr. Farmer's relation to the electric lighting industry has not been 

 generally known, but it appears that in 1868 he had a dynamo made 

 with which he lighted forty incandescent electric lamps, in multiple 

 arrangement, as is now the practice, and automatically regulated. His 

 lamps were of iridium, which he found to possess the proper electri- 

 cal qualities, but that metal not being found in an available form 

 for commercial use, the system now so common was by him devised 

 vol. xxix. (n. s xxi.) 27 



