re ierunt ei EE 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
n= 20 
n* I0 
  
  
  
T 
1/2 
Fig. 6. Average curves of the standard errors of the y-coordinates of both ways 
triangulated strips of varying lengths. b = d — 0.6h w=1 
seems allowable for the approximate demonstration of the error distri- 
bution to use the average of the standard errors of triangulations in both 
directions. These curves are demonstrated in fig. 5—7. It is also of in- 
terest to determine the mean value M of the standard errors of the coor- 
dinates of the entire strip. The results of such a determination is de- 
monstrated in table 1 for some different lengths of the strip. The 
figures of the table have to be multiplied by the standard error of the 
y-parallax measurements referred to the scale 1:1 (the ground). For 
the standard error 0.01 mm on the image scale 1:20 000 we obtain for 
instance the factor 200 which gives the standard errors of the coordi- 
nates in mm after multiplication with the figures of the table. The-fi- 
gures in parenthesis of table 1 represent the mean values of the stan-