Mine surveying sighting disc, German, 1920-1930
1920-1930
Bronze bench mark, Canadian, 1920-1922
1920-1922
Bronze bench mark, American,1914
1914
First Order bench mark
Angle iron to support levelling staff at bench mark
1914
Nameplate for bench mark, British, 1914
1914
Bolt forming one concealed reference point at a fundamental bench mark
Bolt forming upper reference point on top of granite pillar at fundamental bench mark
Cast iron bench mark, French, 1910-1914
1910-1914
Cast iron bench mark, French, 1914
1914
Second Order bench mark, Survey of Egypt, c. 1920
Traverse mark, bolt and cover, British, 1910-1914
1910-1914
Iron bracket for use with Bench mark, British, 1914
1914
Mining surveying level target, British,1930
1930
Bench mark and bracket for surveying staff
1970-1975
Bracket for use with level on bench mark, British, 1914
1914