(413) 
THE NEW MAP OF THE GRAND DUCHY OF LUXEMBURG 
After having explained in what conditions the Luxemburg authorities in- 
troduced the idea of a modern map of their country, the report discusses some 
of the methods of making the survey of this map which could be executed by 
the French Institut Geographique National. 
It (the report) stresses in particular on the delays hampering a very rapid 
execution of the work as the photographs were taken in late April 1951, that 
the preparation on the ground began late in May, that the plotting work began 
in September 1951, and ended in May 1952. The work of completion was in 
progress during the summer of 1952; at the end of October all the data can be 
delivered to the cartographic services who are executing the 1/10,000 and 
1/25,000 editions. 
Thus, in about two years, all the work of surveying and editing concerned 
in this territory of 2600 km? will have been well arranged, from the taking of 
the photographs to the publication of the maps. 
It should further be emphasized that the City of Luxemburg and its 
environs were treated in a special manner in taking the photographs and in 
compilation at 1/10,000 scale. 
The report gives us the statistical information on the work and explains 
how the conditions of the organization of the work of the Photogrammetric 
Service of the Institut Geographique National permitted the execution with 
neither delays nor restrictions. 
PHOTOGRAMMETRY AT THE INSTITUT 
GEOGRAPHIQUE NATIONAL 
After several thoughts on the installation of the Photogrammetric Service 
in the new location at Saint Mande and on the fact that Photogrammetry must 
be considered not as an idea in itself, but as an economical method for solving 
various problems of topographic surveying, the report points out the interest 
of aerial photography as a record of work replacing the map when none exists, 
or even as an aid for certain special studies, which justifies considerable effort 
made by various nations for obtaining very quickly a periodic, systematic 
coverage of their territory. 
The text returns afterwards more in detail to all the thoughts intervening 
in the fixed methods for the practical execution of a survey at a given scale, 
after having satisfied the limits of well-determined accuracy; the choice of the 
photographic material, film or glass plates; the scale of the negatives, the photo- 
graphic material used in the plotting device; research in all the stages of mapping 
at a consistent accuracy and the use at which the resulting map is to be placed, 
especially those things that are concerned with the elimination of the effects of 
distortion. 
The report goes on to explain how on the basis of these theoretical ideas, 
the Institut Geographique National has found a way to organize the photogram- 
metric work on a factory production system, urging as much as possible a