“8 = 
to observe regular recurrehcies in investigating photogrammetrie 
laws, on the other hand, to take into consideration the corre- 
sponding practical objectives of research. In the so-called devel- 
oped countries this is not possible in general, and therefore 
only two options are available: either direct simulation or the 
real problems of developing countries. 
It is in the developing countries, in particular, that large 
areas are being mapped by using photogrammetric methods. These 
mapping projects and the material used in them help promote 
photogrammetric research. 
With reference to the above, it might be stated that photogrammet- 
ric research has unknowingly been lead into solving the problems 
of developing countries, because these, in turn, offer the most 
promising practical objectives of research. Just as in space 
research, information, useful in solving theoretical problems and 
in developing the science in the host country, is obtained as 
a by-product. 
In discussing activities concerning the developing countries, they 
are often identified with assistance. It may well be said that 
dealing with the problems of developing countries contributes to 
the development of photogrammetric research. However, it is not 
quite clear which party is the donor and which party the receiver, 
or whether both parties are in need of assistance. 
With reference to the above arguments, there are excellent reasons