facility on all configurations of their new System/360. 
Essentially all the current practical users of analytic 
systems employ medium or small computers. It has been clearly 
demonstrated, however, that the largest computer is not only 
faster but also cheaper, especially if the program consumes a 
large percentage of the available time on the small computer. 
For example, a job that may require 10 hours on a small 
computer charging $11 per hour for a total of $110 may require 
less than one minute on a large computer charging $1200 per 
hour for a total of only $20. The problem becomes particularly 
significant in the block adjustment program. Consequently, 
a pure rigorous photogramme trie block adjustment becomes 
entirely practical if a large, fast computer is readily 
available. 
Satellite Geodesy 
The subject is dealt with in Commissions II and VII and 
is not repeated here other than to state that the experience 
gained in that effort has been exploited profitably in analytic 
aerotriangulation. for topographic mapping. Satellite geodesy 
has been supported by national programs with an intensity far 
greater than would be possible for topographic mapping. 
It may be of interest that in C&GS satellite geodesy and 
analytic topographic aero triangulation are performed by the 
same personnel on the same instruments and the same computers 
in the area of the Photogramme try Division. 
It seems, therefore, that satellite geodesy ought to 
be in Commission III, and I wish to take this opportunity 
to urge that this Congress consider such a change. 
The Analytical Plotter 
The Analytical Plotter is on display in the Exhibit Hall. 
The U.S. Air Force was instrumental in providing the impetus 
for the development of the inventor's (Mr. U.N. Helava, 
National Research Council of Canada) ideas and the manufacture 
by 0MI in Italy. The instrument has at least three modes of 
operation: a stereocomparator, a first-order stereo triangulation 
instrument, and a stereo compilation instrument. In its compila 
tion mode particularly, it utilizes an intriguing combination 
of analog and digital photogrammetry through the application 
of an on-line computer. It too has succeeded in removing 
many of the restrictions of accuracy inherent in the conventional 
stereotriangulation and stereo plotting instruments. 
Automatic Mapping 
Numerous efforts have been pursued in the U.S.A. on 
specific phases of an automatic contouring machine. Mr. John V. 
Sharp of IBM (present chairman of the American Committee 
on Computational Photogrammetry) is presenting a paper in 
Commission II on such a device, as is Mr. R. D. Es ten. 
Mr. Sharp's solution is digital, utilizing the fundamental 
mathematical principles of analytic photogrammetry.