3 GREAT BRITAIN 
REPORT OF THE DIRECTORATE OF COLONIAL SURVEYS 
A) a) Stereo pairs. 
b) Normally the contact scale of the photography is 1:30 000. 
Planimetry is supplied by Slotted Template adjustment and detail 
plotting by radial triangulation at mean photo scale. 
Contouring by Multiplex at 1:12 500. 
Publication scale of maps 1:50 000. 
c) Vertical interval between contours must vary with the nature 
of the country being mapped. If the country is not too steep 50 ft can 
be taken as the normal V.I. 
d) Any which may be available or obtained by field surveyors 
of the Directorate in the time available. Radar is sometimes used. 
e) General plotting accuracy 0,5 mm at compilation stage. Con- 
tours probably accurate to half a contour interval. 
f) Topographical for planning development. Also to carry addi- 
tional e.g. Geological Forestry, soils, information. 
g) Normally no large or medium scale maps exist, revision does 
not therefore arise. 
B) 1. a) A few town plans and small islands have been mapped. 
b) 1:5 000 and 1:10 000. 
Some on A 5, some Multiplex, some Multiplex and graphical. These 
plans are normally based upon ample ground control and have a good 
standard of accuracy. Contour interval of the order of 1:1000 flying height. 
c) See answer to À g) above. 
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