points in each stereoscopic model were determined as to the heights, 4 
of them surrounding the area to be mapped and one situated in the middle 
of the model. 
For the planning of certain military constructions maps on the sca- 
les of 1:1000-1:10 000 were made by plotting stereoscopical pictures in 
Stereoplanigraph, Wild A 5 and A 6. 
II. The Central Office of the Land Survey District Organization pro- 
duces a map 1:4000 as a basis for estimation of damage in connection 
with the damming up of a river for the building of a powerstation. The 
geodetic net-works were made in the form of local triangulations bound 
together with specially formed traverses. The damming line, certains 
boundary-points and passpoints were signalled before taking the air- 
photographs. The stereoplotting was made per picture pair in a Wild A 5. 
As a basis for the urban planning of an area damaged by earthslip, 
a map was compiled on a scale of 1:2000. 
ILL. The Water-Power Board uses photographs, mosaics, photo-maps 
and also drawn maps for preliminary planning of power-stations and for 
the projecting of dams, for preliminary examinations of earth-damages, 
for the planning of power-lines and for records research about land esta- 
tes, especially over river-stretches. 
The scales are 1:2000-1:4000 for dams, power-stations and detailed 
mapping, 1:10 000 for ordinary maps and 1:20 000 for powerlines and 
very preliminary mapping. 
Arable land was usually mapped according to classical methods. 
IV. The Public Organization for Highways and Hydraulic Structures 
has as an experiment used photographs and photo-maps for the plan- 
ning of roads. 
V. The Royal Telegraph Service makes much use of photomaps and 
mosalcs for projecting of new cable- and telephonelines. 
b) Region- and townplanning. 
The Geographical Survey Office has produced the following types 
of base-maps to General plans of towns, local government-areas and rural 
communes. 
Region- and generalplans for large areas. The Photo-Map 1:10 000 
with or without contours and with an interval of 5 meters is used. The 
net-work is obtained through triangulation in Multiplex or Wild A 6. 
Pass points are signalled and certain points are determined as to their 
heights. At the photointerpretation the details are drawn on to redtoned 
photographs and are then drawn fair. These details are printed on to 
plastic sheets so called « blackprints», on which the photopicture has 
been removed. 
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