445 
The following definitions have been used: 
N 91 
= 
+ dx'i 
- dx' 3 
+ dx' 4 
— 
dx' 6 
+ dx' 7 
— dx' 9 
+ 
+ dy'i 
+ 
dy' 2 + 
dy's — 
dy'7 — 
• dy 
f ^ 
dy'o 
n 92 
= 
+ dx' 4 
+ dx' 2 
+ dx' 3 
— 
dx' 7 
— dx' 8 
— dx' 9 
— 
- d/i 
+ 
dy' 3 - 
dy' 4 + 
dy' 6 — 
dy' 
7 
dy' 9 
N 93 
= 
+ dx'i 
+ dx' 3 
+ dx' 4 
+ 
dx' 6 
+ dx' 7 
+ dx' 9 
+ dy'r 
dy' 3 - 
dy' 7 + 
dy'g 
n 94 
= 
+ dx'i 
- dx' 3 
— dx' 7 
+ 
dx' 9 
+ dy' 4 
+ dy' 2 
+ 
+ dy' 3 + dy' 7 + dy' 8 + dy' 9 (9) 
The coefficients for computing the x-obliquity and the width-error 
are given in the table No. 1. 
2.2 The autograph A8. 
The x-obliquity and the width-error can be computed also for the 
autograph A8 according to the same principle as for the autograph 
A7. The points are located according to Fig. 2. As the base cannot be 
adjusted into position zero, shorter distances than those in the auto 
graph A7 must be used in the x-direction. a 4 is chosen to be 60 mm, 
a 2 100 mm and the base 80 mm. The following results are obtained 
after forming and solving the normal equations: 
Fig. 2. Notations and locations of the 
measured points.