NATIONAL REPORT OF THE LAND SURWEY BOARD 
A) MAPS ON SCALE 1:25 000 AND LESS. 
1. The Topographic Map of Sweden 1:100 000 and 1:200 000 is pro- 
duced by the Geographical Survey Office and is a drawn map, containing 
planimetric details and informations as to the heights of certain points. 
For the rest, the height relations are rendered through hachures according 
to Lehmanns method. The draftmap 1:50 000 to these maps is nowadays 
compiled with the aid of the photogrammetrically produced Economic 
Map (B 1. I) or from the Photo-Map, both on scale 1:10 000. The Econo- 
mic Map 1s thereby completed with peat-mosses, marahes, meadow-lands 
etc., which are drawn on to the Economic Map from the Photo-Map ore 
from stereoscopic pictures. 
The Topographie Map is kept up to date by the use of air pictures as 
follows. 
a) If there 1s the Economic Map, it is completed asdescribed above, 
after which it is reduced to scale 1:50 00 and is compared to the Topo- 
graphic Map, enlarged to the same scale. The new details are thereby 
transferred to the old map. Great differences between the two maps are 
corrected by the aid of stereoscopic pictures. 
b) The Photo-Map existing only, its planimetric details are 
pantographed to scale 1:50 000 and are drawn on to the enlarged To- 
pographic Map. 
c) None of these maps exosting, the planimetric details are pan- 
tographed from photographs to scale 1:50 000, after which the details 
are fitted into the enlarged Topographic Map. In some cases sketchmasters 
are used for this purpose. 
The future Topographic Map 1:50 000, will contain both planimetric 
details and contours and will to a larger extent than at present be pro- 
duced through photogrammetric methodes. It is not yet fully decided, 
how it will be shaped. 
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