Accession No
2451
Brief Description
dumpy level, resold by M.D.S. Ltd., English, 1939
Origin
England; London W11; 41 St. James Square
Maker
M. D. S. Ltd. [reseller]
Class
surveying
Earliest Date
1939
Latest Date
1939
Inscription Date
24-3-1939
Material
metal; glass; wood
Dimensions
box length 405mm; breadth 170mm; height 185mm
Special Collection
Provenance
Transferred from Department of Engineering, University of Cambridge, Cambridge, England, 09/1979. Purchased by the Engineering Department in 1939.
Inscription
‘L14 M.D.S. Ltd
LONDON’ (on level)
‘MDS Ltd 41 St James Square London W11
No 158 b Date 24.2.39 Stadia Lines 1:100’ (box)
‘LE’ (lab number)
Description Notes
Metal alloy with dark green finish. Axis clamp. Azimuth motion tangent screw. Rack and pinion focus (broken?) and a secondary eyepiece focus. Bubble mounted on left side with fixed mirror below and winged white plastic reflector above. Graduated bubble. Inverting lens. Cross hairs. 3 foot screws between parallel plates. Ray shade. Fitted wooden box
References
Events
Description
The earliest form of modern surveyor’s level is the ‘Y’ level, which is a telescope supported in Y-shaped bearings. The telescope is held in place by pivoting straps, which allow the telescope to be reversed for back-sighting.
The Y level was unsuitable for difficult colonial terrain, requiring too frequent adjustments and the ‘dumpy’ level was developed in the early 19th century to overcome this. The dumpy level has a much shorter, fixed telescope, which turns about a central axis. It is compact, much more robust and is still being used in largely unaltered form on building sites and in road construction.
31/08/2006
Created by: updated by Ruth Horry on 31/08/2006
FM:42875
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