points with the corresponding actual topographic coordinates, already 
shows the adjustment of the errors introduced on control points perfor- 
med by the photogrammetric proceeding. In fact, the errors found, 
through the plotting, on the control points and on check points, are 
much smaller than those established for the ground control. 
It must be noted that these last errors are much larger than those to be 
expected during the usual working method of ground topographic 
surveys.