No. 2 



HISTORY OF ELECTRIC LIGHT SCHROEDER 



19 



of these lamps were put on exhibition in London, but were not a com- 

 mercial success as they blackened very rapidly. Starr started his 

 return trip to the United States the next year, but died on board the 

 ship when he was but 25 years old. 



OTHER EARLY INCANDESCENT LAMPS 



In 1848 W. E. Staite, who two years previously had made an arc 

 lamp, invented an incandescent lamp. This consisted of a platinum- 

 iridium burner in the shape of an inverted U, covered by a glass globe. 



Staite's Incandescent 

 Lamp, 1848. 



The burner was of platinum 

 and iridium. 



Roberts' Incandescent 

 Lamp, 1852. 



It had a graphite burner oper- 

 ating in vacuum. 



It had a thumb screw for a switch, the whole device being mounted 

 on a bracket which was used for the return wire. E. C. Shepard, 

 another Englishman, obtained a patent two years later on an incan- 

 descent lamp consisting of a weighted hollow charcoal cylinder the 

 end of which pressed against a charcoal cone. Current passing 

 through this high resistance contact, heated the charcoal to incandes- 

 cence. It operated in a glass globe from which the air could be ex- 

 hausted. M. J. Roberts obtained an English patent in 1852 on an 

 incandescent lamp. This had a graphite rod for a burner, which 

 could be renewed, mounted in a glass globe. The globe was cemented 

 to a metallic cap fastened to a piece of pipe through which the air 



