14 
As there are approximately 20 elements in an autograph, it seems suitable 
to use a 99 per cent confidence level (t^ = 2.70). The tolerance limit of 
the adjustment is, therefore, 2.70 • s ^ 0 ^* 
3.2. Experiments. 
A number of experiments have been carried out at the Geographical Survey 
Office of Sweden, whereby several autographs have been checked using this 
method. The computations have been carried out using Forms A7sl> A7:2, A7:3> 
A8:l, A8j2, and A8:3 in the Appendix or on an electronic computer using a 
programme written by J Talts. Thereafter, the autographs were adjusted 
according to Section 1.3* in the Appendix. New measurements were then 
carried out and the results are shown in Tables 7 and 8. Before the adjust 
ment, 31 per cent of the corrections were greater than the tolerance limit 
2.7 * s x , t whereas all the corrections were under this limit after the 
tot’ 
adjustment. In cases where the corrections exceed these limits the adjust 
ment must be repeated. The standard errors of unit weight (s') have been 
about 5-7 ju. m, which is an indication of the geometrical quality of these 
autographs.