8 
in fields different from analogical aerial triangulation 2 . It has been 
made completely automatic, by applying the method of least squares, 
for electronic computation with IBM-650 and IBM-1620 computers. 
The relative programs have been set up by EIRA of Florence. They 
foresee, amongst other things, the possibility of disposing of a total 
of 18 known points (6 in each of the two end bases and 6 along the 
strip) and include the analysis of several residuates. 
3. The appliance of this analytical procedure to planimetric ad 
justment of blocks of strips can obviously only have a purely contingent 
and expeditious character. It should be performed in different successive 
phases and will result convenient only if carried out employing an 
electronic computer. 
As is known, the examination of a block of strips sets some much 
more complex problems than those concerning the study of single strips, 
when performing the error adjustment. The linking, lengthwise in the 
strip and lateral between the single strips, of the various models making 
out the block, must in fact result with no solution of continuity, 
to render univocal the two distinct functions (7) correcting the surfaces 
of error according to X and according to Y. 
The operational practice to be followed to carry out the above 
mentioned procedure, in the case of blocks, provides for an independent 
bridging of each strip and their consequent connection and adjustment 
by applying twice the formulas laid down in the preceding paragraph. 
This will be clearer if we take as a specimen the block of five strips 
(A, B, C, D and E) shown in the figure. 
Consequently, after effecting the preparation of the photographs 
concerning the first strip A, and examining also those of B, we can 
proceed with its bridging, following the direction of the strip and 
basing ourselves on the points known at the beginning. After this 
bridging is completed we shall perform the adjustment of the strip 
itself, according to the above mentioned system, using the known 
points available in the remaining portion of the strip. 
2 The process may be applied also to the transformation of coordinates among 
systems with a different cartographic reference.