Looking rather like a very large set-square, the picture shows one of our Whitaker Gauges in use at our Washford museum.
The Whitaker apparatus – patented by Alfred Whitaker in 1905 whilst he was Locomotive Superintendent of the S&D – enabled the automatic exchange of tablets between signallers and footplate crew without having to slow right down at the beginning and end of each single-track section.
To function correctly, the trackside apparatus has to be adjusted for the correct height and distance from the track and this is what the gauge in the picture assists with. It originated from Stalbridge and is seen here with Trust volunteer Paul Cracknell. Another gauge – also at our museum – was used to set the height of the corresponding apparatus on the locomotive.