120 — 
100 + 
80 4 
n-50 
  
    
  
    
      
  
  
  
T —1 
n n 
8 4 
T T 
n n 2n 3n 7T n 
3 2 3 4 8 
Diagram 16. Ordinary aerial triangulation. Standard errors of the x-coordinates. 
Bridging. s, l. 
weight numbers to (311). It is also evident that these errors frequently 
can be neglected in comparison with the errors originating from the 
y-parallaxes. We will briefly demonstrate the determination of the in- 
fluence of the errors of the measurements in the control points and 
in arbitrary points. 
We assume the control points to be located as follows 
= 07x bn 
(313) 
Yı 0 Yn 0 
The errors of the coordinate measurements are 
du, dy. dx, and dy, 
n 
The influence of these errors upon the elements of transformation 
is found from the expressions (17)—(18). We have the correction ex- 
pressions