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DEFORMATION MEASUREMENTS 
   
  
FtG. 5. A picture of the ship from the phototheodolite and a simultaneously exposed stereo- 
pair of the sea along the ship from the stereocamera. 
others generally used may be summarized 
as follows: 
1. The photography can be accom- 
plished rapidly and without touching 
the object. 
2. The photography registers the posi- 
tion of all points simultaneously. 
3. An arbitrary number of points can be 
used for the measurements. 
4. The measurements are free from 
inertia or friction. 
5. The measurements can be repeated 
and checked at any time that the 
original pictures are available. 
The primary drawback of the photo- 
grammetric method is that the results 
of the measurements are not available as 
soon as the results of direct measuring 
methods. 
DEFORMATIONS OF SHIPS ON THE SEA 
It seems possible that photogrammetric 
methods can be of considerable value for 
measuring deformation of airplanes during 
flight or of ships on the sea. For the latter 
the shape of the waves also can be deter- 
mined easily with the aid of photogram- 
metric methods. 
Figures 4 to 9 inclusive are pictures 
taken as a part of an experiment to deter-