Mining dial in brass of 6.5 in diameter. The tripod legs are in two parts lengthwise being joined by brass screw connectors – the total leg length is 1.42 m with the shorter length being .65 m. The tripod is designed to be used with full or shortened lengths.
For the tripod see https://ice-museum-scotland.hw.ac.uk/product/1977-008-1/.
Possibly used in 1850 for surveying the water tunnel (constructed c.1820) in the Mound Edinburgh.
Mining dials were not just used in mines or other underground locations. They were also used for land surveying.