As promised, here is the guff about the workings of the cable trams.
Cables for the tram run continuously underground. The 'grip man' uses a lever to engage with the cable. At intersections, where cables cross, he has to release and regrip. He also has brakes.
The cables come into the cable house from the various routes and wind about these powered wheels.
These sheaves in the wheel house are not powered but guide the cable to where it needs to go, including around corners.
Other underground sheaves are located as required to guide the cable and make it available for the trams, throughout the route.
The cable tram network was much more extensive but much of it was destroyed by fire and earthquake at different times. The remnant routes are used by a few locals as transport but their main purpose is tourism.
Trolley busses powered by overhead electricity run on rails in other parts of the city. These restored examples can be caught at Fisherman's Wharf. Other more modern trolley busses operate elsewhere.