Craig, hope you don't mind us butting in with what we find on carbon arc lights.
It's a fascinating subject!!
Candy's pictures were great! Here's a little more I found on carbon arc lights:
Street Lights - Charles F Brush
The arc light as a practical illuminating device was invented in 1878 by Charles Brush, a Ohio engineer and graduate of the University of Michigan. Others had attacked the problem of electric lighting, but a lack of suitable carbons stood in the way of their success. Charles Brush made several lamps light in series from one dynamo. The first Brush lights were used for street illumination in Cleveland, Ohio.
Other inventors improved the arc light, but there were drawbacks. For outdoor lighting and for large halls arc lights worked well, but arc lights could not be used in small rooms. Besides, they were in series, that is, the current passed through every lamp in turn, and an accident to one threw the whole series out of action. The whole problem of indoor lighting was to be solved by one of America's most famous inventors, Thomas Edison.