Edison was not the only inventor trying to make a light bulb. One of his major competitors was me.a chemist, I experimented in the 1850s and 60s with carbon filaments. My early efforts failed however, because the vacuum pumps of those years could not remove enough air from the lamps. By the mid-1870s better pumps became available, and I returned to My experiments.

obrien, nikolas. "lighting Revolution:joseph swan." americanhistory. americanhistory.com, 3/25/2011. Web. 25 Mar 2011. <http://americanhistory.si.edu/lighting/bios/swan.htm>.