Museum of the History of Science logo

<< First | < Previous | Next > | Last >>

10 Hanging Miner's Compass

image of Hanging Miner's Compass

image of Hanging Miner's Compass

This is a traditional design of instrument which goes back at least to the 16th century. It was used for surveying and direction finding in underground mines, where there were neither landmarks to sight nor celestial observations to be made. There is an early example as part of a boxed set in the Owners case elsewhere in this gallery.

In use, the instrument would be hung from a cord set up along the length of an underground gallery. Two hooks are attached to the box, one at each end to the pairs of brass pins. The circular brass scale and silvered compass bowl are then rotated together until the north-south meridian line (SE – ME) is aligned with the compass needle. The orientation of the cord line and thus the mine gallery can then be read off from the brass index hand. Rather than being divided in degrees, the brass scale is divided into 24 “hours”. These are simply a convenient way of dividing a circle into equal parts in the mining tradition; the instrument does not tell the time!

The inscription along the edge reads “Johann Oberhayser Vo Schwaz 1765”. Schwaz is in the German Tyrol and the maker Johann Oberhauser is known from at least two other instruments, a theodolite of 1759 and a mathematical instrument set dated 1766, both recorded in Munich.


Collection: Jeff Lock, USA

Objects lent by Jeff Lock, USA:

09. Boxwood Compass, by John Coggs, London, Early 18th Century

45. Boxwood Diptych Dial, Attributed to Henry Sutton, English, 17th Century

Back to top