Chapter 5 explores electric lighting and its effects on health. Scientists experimented with artificial light for years before Thomas Edison invented the lightbulb. Edison is celebrated as the inventor of artificial light. As Ramirez explains, however, Edison’s light bulb would not have been possible without William Wallace, the creator of the carbon arc lamp. Wallace’s lamp functioned by passing electricity over two thick carbon wires, resulting in an overly bright light that burned out too soon after contact with oxygen.

Edison’s breakthrough came in September 1878, after a visit to Wallace’s home. Wallace unexpectedly received a telegram from Edison asking to see his newest invention—the carbon arc lamp. Edison appeared at Wallace’s home a few days later with several prominent scientists and a reporter from the New York Sun. Wallace and Edison discussed their shared hope of creating new forms of illumination before Wallace took the group to his third-floor lab for a demonstration. Captivated by the carbon arc lamp, Edison pored over Wallace’s diagrams before rushing home to experiment with his own system of artificial light, which drew heavily on Wallace’s. The respect and recognition Wallace long dreamed of seemed to be within reach. What Wallace failed to anticipate, however, was Edison running with his idea and cutting him out entirely: “September 8, 1878, was supposed to be the best day of William Wallace’s life.