174
are also represented in fig. 8 and expressed in mm under the
assumption that the length of the base is 500 m.
A systematic error in the triangulation in consequence of the
secundary rotations is therefore out of question.
The accidental errors caused by this source can be neglected since
d
they correspond with an error of ca 1 micron on the scale of the
photographs.
In general may therefore be concluded that the guide-rules for the
X-movement and the guiding wheels are constructed with a sufficient
accuracy.
a
Zeiss
b
Left
c
Right
Left I
De Koningh Nr3975<
/Right
De Koningh Nr39S5
'LeFt i
t 10 dmgr
Circumference of wheels
1 cm
Fig. S
