— It was necessary to form a great administrative system in order to manage the enor- 
mous number of crews, with complications in cost easily stated. Thus each ten crews 
should have a supervisor each ten supervisors a chief and each certain number of 
supervisor a division leader; this would immediately cause the signing up of more ad- 
ministrative personnel, offices, telephone services, and so on. 
Every crew would need an initial investment of about $ 4,800.00 U.S.Cy., since they 
would need to buy transport, theodolite, temporary housing and camping equipment. 
Irrespective of cost it was brought that the crew would travel slowly on the lands under 
study and thus giving time to the owners to fight back their presence. 
Continuing with the analysis it was considered that the crew work results would be recorded 
in field books and then in drawings, which are not easy to understand and which need 
to be adjusted to a general plan. Nevertheless, it was also mentioned that crews carry 
out their work regardless of climatic setbacks. 
We can make a summary of the previous points by saying that land methods are not 
only considered costly and lengthy but it was also decided during the discussion that it 
was impossible for the country to organize a working team of such magnitude dedicated 
to localization only thus detracting them from other productive activities. 
2. 
PHOTOGRAMMETRIC METHODS. Government enterprises and private firms were analy- 
zed to assess their capacity for work in the field of photogrammetry substracting from 
their potential capacities all those unavoidable commitments. 
Thus it was found that there was ample capacity to carry out this work, within the pro- 
per limit of time. Another favórable factor was the finding of a large number of photo- 
graphic mosaics, which concern areas that had been previously surveyed by government as 
well 
as private firms. Nevertheless it was discovered that the labor force available for 
making out mosaics was lower than required, but it was also noted that they had a whole 
year to train specialists in this field,since, if the photographic method were to be adop- 
ted, one would begin by studying those areas already surveyed and by photographing those 
not existing in the files, thus having enough time to create a corp of assistents. 
When we talk of the limitations imposed by the physical conditions of the country in the 
carrying out of large scale topography, some references were made to the advantages of 
photogrammetry on the one hand and the advantages of traditional methods on the other. 
Here it would be convenient to further examine some of the obstacles for the application 
of photogrammetric methods and to later on point out some of the traditional advantages 
of these methods in order to obtain a complete picture. 
As disadvantages the following are quoted: 
Due to the cloudiness of large tracts land through the country and the effects of burning 
off, we have very few days in which we can photograph, which, makes it necessary to in- 
crease the number of required airplanes. Nevertheless, the Companía Mexicana Aerofoto, S. A., 
using all its experience in the projects carried out in previous years, drew up a system to 
overcome this disadvantage which was tantamount to multiplying the number of airplanes. 
Knowing the different characteristics of the Mexican territory, it was possible to zone 
it and basing aurselves on this division, to establish a system of complimentary bases, 
where the airplanes depending on these bases were left to stanby ready to go to regions 
where climatic conditions would permit flights before this, if the meteorological condi- 
tions did not allow it, the airplanes remained inactively grounded. With the special program- 
ming of the Compania Mexicana Aerofoto, S. A., flights and due to the fact that the 
Agrarian Department considered the management of large surfaces, it was possible to 
keep the flight equipment under use all the time, this fact thus diminishing costs and 
cutting down the necessary time to carry out the task. 
  
(1) 
This can be explained considering the difficulty of forming a technical apparatus with 
great’ rapidity and without prior preparation.