Oldest Verifiable Manhole Cover in the City

[Brock7]

Edison Illuminating Co.? What's the safety pin for? - that thing needs to be bolted down.

[Jimaz]

Edison Illuminating Co.? What's the safety pin for? - that thing needs to be bolted down.

Good job. Considering the wear it's amazing anyone could read that. I couldn't.

From DTE Energy, The Early Years:

In 1886, the Edison Illuminating Co. of Detroit was organized and began serving its first customers. By 1892, the company's customer base had grown to 550, with many of its customers involved in the production of railroad cars, ship engines and cast-iron stoves. In that pre-automobile industry era, Henry Ford worked for Edison Illuminating, first as a night fireman and engineer at $40 a month and later as chief engineer at $100 a month.

By the turn of the century, the Edison Illuminating Co. and the Peninsular Electric Light Co. [[which owned the electric distribution franchise in the area) provided all commercial electric lighting and power in the city of Detroit. In January 1903, Detroit Edison purchased securities of the two companies and incorporated on Jan. 17, 1903. That same year, construction began on the Delray 1 power plant, and Henry Ford, who had left Edison Illuminating four years earlier, founded Ford Motor Co.