B) TERRESTRIAL PHOTOGRAMMETRY 
An increasing use is being successfully made of terrestrial photogrammetry 
in the preparation of large scale maps for dam sites, archeological studies, map 
completion etc. 
C) PROVISION OF PHOTOGRAMMETRIC CONTROL 
The necessary control for orientation of stereograms for photogrammetric 
restitution is provided either by field surveys or a combination of field control 
and aerotriangulation adjusted in strips or blocks. Both the methods of aero- 
polygon extension and independent models for strip and block adjustment to 
gorund control are used. 
The I. T.C. Jerie Analogue Computer System of block adjustment is 
used in flatter areas such as for irrigation works. For hilly or mountainous 
areas a variety of computer facilities are available and include I. B. M. 1130, 
1620, 7040, 360/40 and 360/65 machines. Programmes used for all forms of 
adjustment are mainly those prepared and written by Dr. C. W. B. King. 
D) PROJECT MAPPING 
A wide variety of different scales and types of mapping is undertaken 
by the National Cartographic Center as demanded by all forms of development 
projects. Scales vary from 1/200 to 1/50, 000 and are used for study, planning 
and execution of hydroelectric and irrigation schemes, transmission line net- 
works, urban development, mineral exploration, pipelines, highways, etc. 
The following details indicate the scope and extent of the activities of 
National Cartographic Center and the Private Companies over the past 4 years. 
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