was concerned, where they resulted very small for over three quarters 
of the total lenght of the strip. 
It is evident that the use of the control device is not indispensable 
in instrumental bridgings. It seems to acquire a great interest only when 
the control of the azimuth become particularly important, as happens 
in the case of solar aerial triangulation. 
In many instances the use of suitable levels may effectively sub 
stitute the advantages offered by the use of this device in controlling 
the co and 9 parameters during the transfer from one camera to another. 
The procedure followed in that case will have to take into consideration 
the coordinates of the pass points to reimpose the third and last 
parameter x. 
An appliance of the latter type was successfully effected, as far as 
we know, by the photogrammetric section of Iran irrigation on the 
behalf of the Iranian Oil Exploration and Producing Company of Teh 
ran, for the analogical bridging at a model III Galileo-Santoni Stereo- 
simplex (rag. No. 00111) of three super wideangle strips (f = 88,48 
mm and size 23X23 sq. cm.), consisting of 3 and 9 photographs respec 
tively at an average scale of 1:75 000. 
The examination of these super-wideangle photographs at the normal 
Stereosimplex III, allowed by the morphology of the ground which was 
mostly flat, permitted to determine on such an occasion as many as 200 
photographic minor control points used later for the plotting of a block 
of strips made out of photographs at the average scale of about 1: 30 000. 
The author expresses his gratitude for the facilities provided by EIRA 
of Florence. 
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