Hinks, Arthur R. (Arthur Robert), 1873-1945 · Cambridge, University press · leaf 150
an iron gate, or taking bearings from the point of vantage thata bridge over a railway gives. Such mistakes are, of course,soon realised and avoided; but it is not so easy to guard againstless obvious sources of error, such as a water main under theroad. Should there be any suspicion that abnormal… … I. Prismatic Compass. Mark VI. Opened out flat.
Maps · Surveying
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