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we know now, there are some objections against measuring with such long 
wavelengths that are necessary with the ordinary radar methods today availa 
ble. If we should like to make a computation of the relation between the 
diameter of our reflecting system, in the case where we have an optical system 
and in the case where we have a radar system, we find that we have to go to 
a diameter of not more than 300 meters in order to get something similar to 
what we have in the optical system, where we have a diameter of 3 dcm. That 
means that it is absolutely impossible to get a system of similar accuracy. But 
now we have heard of extremely high accuracy and I should be interested to 
know if this accuracy is really verified over all different types of land, over 
woods, over hills, all over, I mean, because it is well-known that it is easy to 
obtain a high reading-off accuracy but it is hard to make an accurate determina 
tion of the velocity of the electrical waves. This problem we have whichever 
method we choose. We still have it as long as we are operating with these few 
electronic methods. So, as far as I understand, the question is not the invention 
in itself, the question is to find the real velocity of the waves we are working 
with. I should like to know if there is something new about this part of the 
question which is almost the most interesting, but I should also like to add 
that certainly we know very well that electronic equipments under special 
circumstances are quite sufficient for example for photogrammetric work and 
I think that this new device is exactly what is wanted to fill out the range 
above light radar and ordinary radar. 
L'heure étant venue de quitter la salle, la suite de la discussion est remise 
au lendemain, à la fin de la session des résolutions, s’il reste du temps libre. 
Le Prof. A. Bjerhammar souligne la différence de dimensions des systèmes réflecteurs des 
procédés électroniques (300 mètres de diamètre) et optiques (30 cm). Il se demande si la précision 
dont on a parlé est valable sur des terrains accidentés ou couverts, car il doit y être difficile de 
connaître la vitesse exacte de propagation des ondes électriques. Il admet que les procédés 
électroniques doivent souvent suffire en photogrammétrie. 
Session des résolutions: le jeudi 26 juillet 
de 9h.OO à 9h.55 
Bien que le début de la session ait été effectivement consacré à l’étude et au 
vote des résolutions, il sera d’abord rendu compte ici des discussions qui, en fin 
de séance, ont prolongé les sessions techniques, ceci afin de clore logiquement 
le procès-verbal par l’énoncé et la discussion des résolutions adoptées par la 
Commission I. 
M. J. Cruset: A la dernière séance, lors de la discussion de la communication 
de M. Konchine, il y a eu, m’a-t-il semblé une certaine incompréhension en ce 
qui concerne les radio-altimètres, venant peut-être d’une confusion entre le 
champ propre instantané de ces appareils et l’amplitude de leur balayage. Je ne 
veux pas répondre, peut-être en me trompant d’ailleurs, à la place du Prof. 
Konchine et je lui donne la parole. 
In spite of the fact that the meeting dealt first of all with the resolutions, a record will be 
given here of the discussions which took place at the end of this same meeting, but are in fact a 
follow up of technical meetings. This allows to give at the end of these minutes, logically, an 
account of resolutions and their discussion. M. Cruset states that there seems to have been some 
confusion, in the discussion of Prof. Konchin’s paper at the last meeting. Prof. Konchin will now 
give an answer himself.