6. 
39 
Difficulties of the terrain and some uncertainties in the identification of signali- 
zed points have not always permitted to keep to the theoretical criteria adopted 
with respect to their distribution on the terrain. 
However, we wish to stress that the work carried out by Prof. Neumaier is of 
excellent quality. He has completed it very quickly and has overcome many diffi- 
culties during the preparation and distribution of the material. Furthermore we 
wish to thank him very sincerely for his offer to execute on the punch-card 
machines which he has available, the provisional compensation of the triangula- 
tions to be completed in :he course of the next few months. 
Control of the cameras. 
The control of the cameras used for Comm. B. has been organized and e recuted 
before and after the flights, in a similar way to that carried out for Comin. A. 
The tests were executed according to the rules given by the Comité Directeur. 
The results have been communicated to the Centres in time for the beginning of 
the work. 
Flight index maps and preparation of diapositives. 
The Centre in Vienna has made the flight index maps of the first group and the 
preparation of the copies which were sent to the Centres. The making of glass 
diapositives from the original negatives has also been done in Vienna. A very 
strange phenomenon of “reticulation” of the emulsion was observed on some dia- 
positives during the restitution and it was necessary to make new copies. 
In general the results of the photographs of the first and second group taken in 
June 1954 are satisfactory, although the atmospheric conditions of the zone and 
the winds made it impossible to obtain strips of a perfect regularity, especially 
in respect of the lateral overlap. 
The last flights of the 3rd group carried out in November-December 1955 are 
perhaps not much different. Nevertheless, we hope that it will provide us with 
valuable test material for the work which will be continued in the course of the 
year 1956 and later. 
The reading of the values of the statoscopic data and their distribution have been 
entrusted to the Photogrammetric Institute of the Technical University in Ziirich. 
It has not been considered necessary to prick points for the work of Comm. B. 
As a matter of fact the relatively large scale of the photographs usually allows 
a good identification of details, interesting for the restitution. 
General instructions for triangulation work on large scales. 
The variety of means and conditions which could be applied to the work in the 
Centres of the various countries, who have accepted to contribute to the work of 
the OEEPE would certainly not have lead to comparable results, owing to the 
lack of homogenity, if not a severe discipline and precise instructions within the 
scope of the Organization had been established. 
Based on the principles, thoroughly examined before the beginning of the work 
by the members of the Commission and by the Comité Directeur, it was easy for 
the President to draw up provisional instructions for the tests in question. 
A draft text of these instructions has been sent to the members of the Commis- 
sion with a view to submit it to a detailed examination and to obtain advices and 
suggestions. 
One has tried to standardize as much as possible the principles of a general nature 
or common to Commission A and B. On the other hand the differences existing 
between the triangulations to be carried out in the two Commissions have been