76 
dx, = — dx, 
dy, = — dy, 
db (314) 
dx, = — dx, — bn — 
b 
dy, = — dy, — bndx 
Consequently 
da, — — da, 
dy, — — dy, 
dx, — dz, Dir 
db == (315) 
n 
dy, — dy, 
de = : 
bn 
Hence the corrections dx and dy in an arbitrary point with the coordi- 
nates pb,0 are found from (17)— (18) 
P 
dx = — dx, + (dx, — dx,) 
n 
D 
dy = — dy, + (dy, — dy,) 
n 
or, including the measuring errors dz, dy, 
) ) 
daz da, | E um ) zd dz, + dz, 
) 
2 n n 
(316) 
p p 
dy — dy, | — 1] — dy, + dy, 
n n 
Assuming the standard error of all coordinate measurements to be 
equal we find the weight numbers 
(p — nf p? 
Qu P Qu = n? T n? E I 
or (317) 
Qu =0=2(5- 241