20 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 76 



could be exhausted. After being exhausted, the pipe, having a stop 

 cock, could be screwed on a stand to support the lamp. 



Moses G. Farmer, a professor at the Naval Training Station at 

 Newport, Rhode Island, lighted the parlor of his home at 11 Pearl 

 Street, Salem, Mass., during July, 1859, with several incandescent 

 lamps having a strip of platinum for the burner. The novel feature 

 of this lamp was that the platinum strip was narrower at the termi- 

 nals than in the center. Heat is conducted away from the terminals 

 and by making the burner thin at these points, the greater resistance 



Farmer's Incandescent Lamp, 1859. 



This experimental platinum lamp was made by Professor Farmer 

 and several of them lighted the parlor of his home in Salem, 

 Mass. 



of the ends of the burner absorbed more electrical energy thus off- 

 setting the heat being conducted away. This made a more uniform 

 degree of incandescence throughout the length of the burner, and 

 Prof. Farmer obtained a patent on this principle many years later 

 (1882). 



FURTHER ARC LAMP DEVELOPMENTS 



During the ten years, 1850 to i860, several inventors developed 

 arc lamp mechanisms. Among them was M. J. Roberts, who had 

 invented the graphite incandescent lamp. In Roberts' arc lamp, 

 which he patented in 1852, the lower carbon was stationary. The 

 upper carbon fitted snugly into an iron tube. In the tube was a brass 

 covered iron rod, which by its weight could push the upper carbon 



