Signalisation 
Signalisation of all control points, boundary marks not determined by 
coordinates, water wells, manhole covers, telegraph and electricity mains, 
and certain other constructions was to be carried out. 
The signals were either to consist of white-painted masonite plates or 
were to be indicated by paint applied direct on the various objects. The 
size of the signals was set at 30 7X 30 cm. 
Stereo plotting, drawing and reproduction 
On account of the density of the control points, each stereo model 
could be oriented independently. The compilation was to be done in 
pencil upon a sheet on which the planimetric details, contour lines, 
control points, boundary marks and all the other signalled objects were to 
be plotted. As material for the maps, transparent plastic sheets of the make 
Cronaflex were chosen. 
The manuscripts procured in this way were then to be drawn in a 
final copy and reproduced in such an order that the various purchasers 
received maps with the contents they desired. 
Picture No. 2 shows how the map distribution from the manuscript to 
the City Engineer Office, the Building Office, the Electricity and Tele- 
phone Works, as well as the town planners was to function. 
Views on the technique employed 
As already mentioned, the mapping work was started in the spring of 
1967. 'The experiences of the technique employed are good. Colour film 
has proved to give better interpretation of photographs than panchromatic 
film would have permitted. The stereooperators consider colour film 
superior to panchromatic film also from the view point that the work is 
less tiring. 
What appears less rational from a technical point of view in the pro- 
cedure mentioned, is the relatively extensive geodetic measuring of 
control points. 
Further, during the past year, in connection with the Huddinge pro- 
ject and other projects of a similar nature, the suitability of choosing the 
flying altitude 600 metres for work of this kind has been the subject of 
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