VARIATION ON THE SCALES OF PARAMETER to, 9, x 
OF THE LEFTHAND CAMERA BY MEANS OF THE CONTROL DEVICE 
Photograph: 
A co 
A 9 
A x 
C 
c 
c 
2 
0,0 
0,0 
0,0 
3 
+ 0,6 
0,0 
—0,3 
4 
+ 0,7 
0,0 
—0,6 
5 
+ +0 
+ 0,3 
—1,0 
6 
+ 1,0 
—0,2 
—0,8 
7 
+ 0,8 
—0,2 
—1,0 
8 
+ 0,6 
0,0 
—0,6 
9 
+ 1,0 
-0,5 
—0,8 
10 
+ 1,0 
—0,5 
—0,4 
After completing the test concerning the control device we repeated 
the ten grid bridgings by means of the simple visual transfer, from 
the righthand to the lefthand camera, of the three parameters w, 9, x 
of the outside angle orientation. Of course during this second test we 
kept unaltered the ideal technical features taken on in precedence. 
The results attained in these two bridgings are shown on plate 
No. 1. 
The examination of this plate clearly indicates that the intervention 
of the control device resulted particularly effective as compared with 
the simple visual transfer of the three parameters concerned, in trans 
ferring the azimuth from one stereogram to another along the whole strip. 
In both bridgings after the fifth connextion we registered, as appears 
evident, an almost identical fall of altitude, which in the former how 
ever was accompanied by an increasing and noticeable warping of the 
resulting space model. The latter circumstance is perhaps partly to be 
justified by the systematic correction of about I e which was in fact 
introduced from the fifth photograph onwards on the to of the control 
device, and partly residuate errors in the geometric condition of 
the instrument. 
Logically, the observations derived from these two pilot tests allowed 
further to refine the instrument adjustments carried out in advance on 
the device itself, allowing also to devise some means to improve the 
operational practice followed in the next bridging of real photographs.