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Mora. Most of the material is simply compiled for further work. The planning 
and recording of field work is carried out with the aid of aerial pictures. 
Momuments and other works of art as well as buildings are recorded in the 
same way for photogrammetric plotting, as part of the training at the Division 
of Photogrammetry (HIT). As this training is differently placed each year an 
increasing material for such studies is obtained. 
Of special interest is an application of photogrammetry to the solving of 
certain riddles connected with an old picture of the dome of Upsala. The work 
was conducted by Dr. P. O. Fagerholm. The perspective of the picture was 
investigated through comparison Avith new geodetic measurements and the 
center of perspective was thus located. The analysis of the projection was 
simplified by using a new instrument for making perspective drawings, Auto- 
perspect, constructed by Mr. W. Sundstrbm. 
2) Deformation measurements. 
The Division of Photogrammetry (RIT) has continued the work in this field 
reported at the VII Congress in Washington. Single picture methods are used 
for measuring of the deflection of bridges under load. Some Avork has been done 
on the refinement of this method, chiefly through appropriate marking of the 
measuring points, but also through some theoretic developments for proper 
computations. This line of work is exemplified through experiments on the 
wing of a model airplane. At all points to be measured, small steel balls were 
glued to the wing and the image of a flash rendered good definition in these 
points. The possibilities of this method is clarified by subsequent work at the 
Staff of Defence Avhere Mr. P. Hjelmstrom has continued research. As an example 
of deformation measurements with compensation for movements of the camera 
may be mentioned experiments by Professor B. Hallert and Dr. P. 0. Fagerholm 
concerning the deformation of ships at sea. 
Literature: 
Bertil Hallert: Deformation measurements by Photogrammetric methods. Photogrammetric Eng. 
Dec. 1954). 
P. Hjelmstrom: Noggrann deformationsmatning med hjalp av fotogrammetri. Fotogrammetriska 
meddelanden II/3, 17 s. 
B) Criminalistics 
For the purpose of recording position and speed of cars a photogrammetric 
method has been used. A police car Avas equipped with a suitably mounted 
miniature camera of the Robot type, which gave serial pictures on 35 mm film. 
The negatives are measured in a stereocomparator. The details Avere Avorked 
out by Mr. E. Rehnlund at the Division of Photogrammetry (RIT). The metric 
properties of the cameras are determined according to Hallert’s grid method. 
Recently the Division of Photogrammetry (RIT) has taken up other problems 
in this field. 
Identification of fingerprints, typewriting and coins and bills by stereoscopic 
comparison is studied. The possibility of demonstrating such specimens to a 
greater audience by means of a stereoprojector has been tried. 
Person identification through some kind of measurement of the head or face 
could be done from short range stereopictures. A Wild stereocamera, 40 cm, 
is used for the purpose, and different modes of eAmluation are considered.