Accession No
2151
Brief Description
Y level by Troughton and Simms, c. 1900
Origin
London; England
Maker
Troughton & Simms
Class
surveying
Earliest Date
1900
Latest Date
1900
Inscription Date
Material
metal (brass, 1 other); glass
Dimensions
length 367mm; breadth 160mm; height 220mm
Special Collection
Provenance
Transferred from Department of Geography, University of Cambridge, Cambridge, England, 05/1969.
Inscription
‘TOUGHTON & SIMMS Ltd
LONDON’ (on Y support)
Description Notes
Metal alloy body with brass screws. Telescope with rack and pinion focusing. Cross-hairs (2 vertical); ray shade. Y supports. Centrally mounted bubble graduated in 1/10´´. Axis clamp; azimuth motion tangent screw. Levelling feet through tribrach limbs.
Condition
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:42893
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