In 1904, the Denver Tramway City Tramway Company decided on an innovative, new plan. During the peak hours, when the extra streetcars normally had to be pressed into service, the company would instead of putting more streetcars out onto the streets, they would attach an un-powered streetcar, called a trailer, to streetcars that were operating on busy rush-hour routes. On the left are the only known color photos of trailers in their original paint configuration. During the 1930s, trailers were taken off the streets. One of these trailers, No. 566, was given by my grandfather, the president of the Tramway, to his best friend, Denver surgeon Edwin Perrott, who installed it in the yard behind his mountain retreat at Glen Elk, Colorado. That's Grandad and Uncle Edwin pictured on the lower left. The top three photos on the right are of trailer No. 605: one of five trailers that survived into the 1940s. These trailers were placed on standard-gauge trucks (wheels) and then assigned to the Tramway-owned standard-gauge D&IM railroad line that ran from Denver to the city of Golden. Trailer 605 can be seen in two of the photos taken in the D&IM yard in Denver, and the last photo shows standard-gauge trailer 617 (one of the five) on dual-gauge track on Arapahoe Street, next to the Tramway's Central Division office building.