3. CANADA
LETTER OF THE DEPARTMENT OF MINES AND TECHNICAL SURVEYS.
Dear Sir:
Your letter requesting certain information on Canadian photogram-
metrical practices for the International Society of Photogrammetry, and
addressed to the Canadian Institute of Surveying and Photogrammetry,
has been referred to this office.
I regret that we cannot give a full answer to your questionnaire,
as our photogrammetrical problems are very different from those of the
highly developed European countries. Most of our mapping 1s for publi-
cation scales of 1:50000 and 1:250000 with à special aeronautical chart
at 1:500000 and very little work 1s done at a larger seale than 1:50000
by Dominion Government Mapping Agencies.
Large scale plans have been compiled by photogrammetrical me-
thods for town planning, irrigation, power development, railroad loca-
tions, mining development and such enterprises with very satisfactory
results. This work is normally done by privately-owned companies and
a list of these will be attached to this letter (*). The equipment they use
will be Kelsh Plotter, Multiplex or Wild A 5 and 6, and Wernstedt-
Mahan Plotter. Apart from these types, I know of no other modern pho-
togrammetrical equipment in use in Canada.
In addition to the topographical mapping carried on by the Depart-
ment of Mines and Technical Surveys and the Department of National
Defence, which departments are closely connected, most of the provinces
undertake their own mapping for such purposes as forestry and land
classification, and utilization. Also, many of the larger commercial enter-
prises carry on considerable photogrammetrical work for planning their
various operations.
It is not possible to say how many maps at a given scale are produ-
ced in a given time as photogrammetry using modern instruments is
still under development in Canada and will be subject to many radical
changes in the near future. To date there are no photogrammetric in-
struments manufactured in Canada.
In conclusion, Canada was one of the first, if not the first, to practise
applied photogrammetry from terrestrial photos under the direction
of the late Dr. E. Deville, Surveyor-General of Canada, and has conti-
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