* 
399 
' *. f 
Williamson 
AIR SURVEY CAMERAS 
and 
PLOTTING EQUIPMENT 
WILLIAMSONS are proud to be the only 
British firm offering a complete range of precise 
air survey instruments. All units from the camera 
to the projectors are carefully matched by in 
dividual calibration. 
Backed by forty years’ experience William 
sons have always been first in the field with new 
developments, and their air survey cameras 
and mapping equipment incorporate the latest 
scientific and technical aids to improved 
operation. 
In Australia and Canada there are resident 
technical experts to instruct in maintenance and 
servicing. Throughout the world Williamson 
representatives are at your service to tell you the 
latest developments of the Company. 
Among users of Williamson photogram- 
metric equipment are the following :— 
★ ★★★★★★★ 
★ ★★★★★★★★★★ 
Hydrographic Department (Admiralty) 
Royal Air Force 
Ministry of Supply. Air Survey Co. Ltd. 
Hunting Aerosurveys Ltd. 
Royal Australian Air Force. 
Adastra Airways (Pty) Ltd., Australia. 
Department of Mines & Resources, Canada. 
Directorate of Colonial Survey. 
Delft University, Holland. 
Royal Dutch Air Force. 
Directorate of Ordnance Survey. 
Army Survey Department, Egypt. 
Greek Department of Works. 
Survey Department, India. 
Survey Department, Burma. 
Bristol University. * 
Royal Canadian Air Force. * 
Geodetic Institute, Denmark. * 
Photographic Survey Corporation, Canada. * 
Directorate of Military Survey. * 
Survey Department, Nigeria. * 
South African Air Force. * 
London University. * 
Manchester University. * 
Dept, of Lands, Queensland, N.S.W., * 
Victoria, West Australia. * 
Survey Department, Pakistan. * 
★ 
WILLIAMSON 
MANUFACTURING COMPANY LTD 
LITCHFIELD GARDENS, LONDON, N.W.10