Miner's surveying compass (mining dial) by Henry Barrow & Co.., 2 Oxenden St., London, England, 1845-1855 Miner's surveying compass, 1845-1855 1845-1855
Mine surveyor's kit, contains hanging compass, hanging clinometer, protractor, ruler, in fitted leather case, 1701-1800 Mine surveyor's kit, 1701-1800 1701-1800
Hedley type mining dial by B. J. Hall and Co., c. 1920 Hedley type mining dial by B. J. Hall and Co. 1920
Lean's mining dial by W. & S. Jones, Holborn, London, 1801-1825 Lean type mining dial, 1801-1825 1801-1825