Lewis Latimer

Latimer was the son of people who had escaped slavery. He taught himself mechanical drawing while working as an office boy in a patent firm, and became good enough at it to draft the drawings for Alexander Graham Bell’s telephone patent.

Working for Hiram Maxim’s electric light company, he patented a process for making carbon filaments in 1882 — filaments that did not break as readily in manufacture and lasted longer in service. Edison’s lamp is the famous one; making the filament practical was a separate problem, and Latimer is one of the people who solved it.

He later worked for Edison, wrote one of the first textbooks on electric lighting, and supervised the installation of lighting in New York, Philadelphia, London and Montreal.

The lamp on this board is the same idea: push current through a thin thread of something that glows without burning away, and keep it in a place where the air cannot reach it.