Model railway speed controller, roller (Bing Table Railway)

From The Brighton Toy and Model Index
Exhibit

Model railway speed controller, roller (Bing Table Railway)

BTMM map 048.gif
location:
Arch Three , Area 48
Bing Table Railway (display)
Shelf 5

An small early 00-gauge trackside speed controller for the Bing Table Railway electric range.

The controller protrudes from the side of a curved section of tinplate three-rail track, and has a raised silver circular lip and a central axle, with a rotating panel with a metal double-roller that presumably makes contact with the metal lip above and some sort of electrically resisting material below, to provide a resistance whose value depends on the position of the rotating section.