The steam engines were replaced by large electric motors that keep the cables moving at a constant 9.5 mph in channels under the streets. The longest of the four loops (California Line) is 21,500 feet of one inch thick braided steel cable. From the observation deck in the power house you can see the large wheels which drive the cables. Other wheels are idlers which guide the cables, or move to take up slack in the loops.

In this photo, the perspective looks distorted, due to the extreme wide angle lens that I had to use.