Among these areas are: 
1. The serial conduct of aerial triangulation in a first 
order plotting instrument. 
2. The orientation of photographs and the plotting of 
planimetry and contour lines in the stereoplotting instrument. 
3. The reading of spot elevations for the determination 
of cross section data. 
To what extent can these operations be automated? Actually 
each of these problems has been attacked, though not directly 
within the framework of a highway design system. 
As a consequence of the application of photogrammetry to 
ballistic missile tracking, elegant digital computation systems 
for conducting aerial triangulation have been devised by Hellmut 
Schmid and Duane Brown. These programs will compute the space 
position and orientation of all photographs in a project 
simultaneously. At the same time they will determine the 
ground survey coordinates of all points whose images have been 
measured on the photographs. The systems are sufficiently 
versatile to include vertical and horizontal ground control 
points, and any auxiliary data controlling the orientation or 
position of the exposure stations. 
The input data for such a system are the image coordinates 
of points measured on the photograph. These are obtained from 
instruments like the Nistri or Wild stereocomparators. These 
machines deliver the photo coordinates on punch cards or tape 
for immediate input to the computer, 
Unfortunately, at the moment, the observation time at such 
an instrument does not differ appreciably from that required at 
a first order plotting instrument. However, progress is being 
made in the automatic matching and marking of images. And 
automatic measuring of well defined point images is already in 
hand. Consequently, one may expect that in the near future the 
human operation will be restricted to the selection of the 
general area on the photograph in which pass points are required 
and to the precise identification of ground control points. 
Another development of compelling interest is illustrated 
in Figure 6. The Automatic Scanning Correlator (AUSCOR), as 
this device was originally called, was designed and built by 
Mr. G. L. Hobrough of Photographic Survey Corporation in Canada. 
Under the name Stereomat it is now being developed by Benson- 
Lehner, 
Basically the Stereomat is a set of attachments to a con- 
ventional double projection stereoplotting instrument. Servo 
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