108 PRESENTATION OF THE GENERAL REPORT 
or details were specifically put for the clear pur- 
pose of collecting all possible technical infor- 
mation on the various working procedures, 
The questionnaire was sent out accompanied 
by a circular letter specifying the Commission’s 
aims and suggesting how best to reply. This 
questionnaire was sent out in November, 1959, 
and sought information relating to the use of 
triangulation from January, 1956, up to the 
end of 1959. Much to this Commission’s great 
satisfaction a wealth of detailed information 
began to pour in from February, 1960. How- 
ever, in spite of repeated requests for a reply, 
both by circulars and personal letters, not all 
questionnaire recipients and, above all, not all 
the Commission’s rapporteurs obliged with a 
reply. The general collection of the replies is 
contained in Table 1 under the caption “Gen- 
eral Information”. As customary the circulars 
were addressed within the spheres of countries 
belonging to the ISP. We must bear in mind, 
however, that vast zones of evidently intense 
photogrammetric activity have been left out 
from the field of information; such zones are 
perhaps the very ones which present a greater 
photogrammetric interest, precisely because an 
ever-increasing need of cartography is felt with 
every day that passes. 
On the whole, replies to the questionnaire 
were exhaustive and fully answered the general 
purpose of the questionnaire itself. We are glad 
to acknowledge this and we wish to thank most 
warmly and publicly all Commission III's rap- 
porteurs in the different countries who have 
most usefully collaborated in the work of the 
Commission. 
The criterion followed for presenting infor- 
mation is the one adopted in almost all preced- 
ing Reports, namely, to condense all infor- 
mation and material into synthetic tables, per- 
mitting immediate vision of the operating va- 
riants of the different procedures. However, it 
was thought preferable to build up considerably 
large tables containing all the information con. 
cerning a specific working procedure in its va. 
rious stages, instead of sub-dividing it into 
several smaller tables. Thus it has made possible 
a correlated examination of the working differ- 
ences in the various stages, namely, to follow 
both through analysis and along the lines in 
columns how procedures change in relation to 
problems particular to each country or agency, 
The tables total seven, the first contains all in- 
formation of a general character, the second, 
third and fourth contain all the other various 
ways of carrying out triangulation, strip, in- 
strumental, analytical and radial ones. The fifth, 
sixth and seventh contain all the different work- 
ing procedures for block triangulation, or in- 
strumental, analytical and radial ones as well. 
Our conclusion can be summarised as 
follows: the analytical triangulation for strips, 
but mainly for blocks, will be the kernel of the 
experimental researches to be carried out in 
future years. This working criterion should 
record also in practice remarkable progress. The 
progress of analytical triangulation will condi- 
tion the development of methods and criteria of 
flight, the choice of cameras and study of para- 
meters, also of their inner orientation, the choice 
of auxiliary equipment and their most fitting 
use and the return to more rigid working 
schemes. The adjustment criteria, after the en- 
couragement due to theoretical researches, 
should lead to more practical methods and with 
more experimental than theoretical justifica- 
tions. 
The precision required in cartography will 
have to adopt itself more closely to the practical 
benefits of aerial triangulation at the cost of 
fictitious requests for impossible precision. In 
the future we shall perhaps see a more wide ap- 
plication of those methods which are now only 
marginal, such as the use of flights at different 
altitudes in order to solve more economically 
many cartographic problems.