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involve, it is desirable that theoretical and practical studies be made in this 
field. 
6. In view of the difficulties caused by the more or less arbitrary choice of 
the positive direction in the elements of orientation in existing plotters, the 
General Assembly recommends: 
a) that constructors of instruments should choose, for their future produc 
tion, a system of coordinates defined by a direct triedre, its origin being at the 
centre of projection and the value Z indicating the projection distance. 
b) that zuriters should choose the sign of the formulae in accordance with 
this system of projection, irrespective of the plotters at their disposal. 
c) that schools should for instructional purposes only use formulae based 
on the introduction of the proposed system of coordinates. 
7. In view of the interest of the experimental tests for the progress of methods 
and instruments, Commission II recommends that the experimental work 
undertaken by the OEEPE should be developed, within the framework of 
collaboration with the ISP. 
The proposal was adopted without discussion. 
§ 3. The Chairman of Commission III, P. Wiser, presented a draft resolu 
tion prepared by the Commission, with the following five points: 
1. Referring to Resolution No. I adopted at the Washington Congress, the 
Commission recommends that before the next Congress, at least one colloquium 
of aerotriangulation be held. 
The Chairman of the Commission, after collecting all the opinions he considers 
useful, will fix the date and place and draw up the agenda and list of persons 
to be invited. 
2. In order to get better results from the working meetings, the Commission 
recommends that General Resolution No. 10 be applied, especially with regard 
to 
a) the selection of the important papers 
b) publication and distribution of papers before the Congress 
c) the treatment of these papers, individually or in groups, by prepared and 
directed discussion, without oral presentation. 
3. The Commission recommends that the controlled tests in aerotriangulation 
be continued during the period 1956—1960 and that the Chairman decide the 
regulations for these, referring to acquired experience and after consultation 
with the principal persons concerned. 
For the present, the Commission finds that there is a general desire: 
a) to maintain the practical character of Test No. 1 in further tests 
b) to continue to give the participants full freedom in the choice of methods 
and means of performing the tests 
c) to cancel the obligation to work on foreign polygons 
d) to achieve, by this relaxation of the regulations, a corresponding im 
provement in the discipline of performance and the possibilities of control. To 
this end, the working documents should be frequently and regularly furnished 
to the director of the test. 
e) that each participant should provide the director of the test with a 
detailed report on the work accomplished. 
4. The Commission notes with satisfaction that good collaboration has been 
established between the OEEPE and the ISP in the field of aerial triangulation. 
It recommends that the experimental studies should be actively pursued and 
extended in this spirit of collaboration.