Like other early inventors, I used a carbon rod with low electrical resistance in My lamp. Due to the relationship between resistance and current, a low resistance element required lots of current in order to become hot and glow. This meant that the conductors bringing electricity to the lamp would have to be relatively short (or impossibly thick), acceptable for an experiment or demonstration, but not for a commercial electrical system.

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