analysis of biological form and function based on principles of analytic 
geometry," can provide an appropriate bridge between the biomedical 
sciences and photogrammetric engineering. As the primary tool of 
biostereometrics, stereophotogrammetry is assured of a vitally important 
role for years to come and, irrespective of any diminution in the 
propriety of imaging techniques, the evolution of photogrammetric 
engineering in theory and practice will constitute a unique and 
continuing resource. 
Measurement, it should be recognized, is but an intermediate step 
in solving biomedical problems. Not knowing what to measure or what 
to do with the results can seriously compromise an otherwise 
appropriate mode of measurement. In many instances where biomedical 
stereophotogrammetry has been used in the past, the choice of what to 
measure is open to reasonable doubt and in some instances the choice 
was plainly inappropriate. Associations between photogrammetrists and 
biomedical investigators have often been short-lived affairs, because the 
biomedical investigator or the photogrammetrist or both were unable to 
devote enough time to thoroughly pursue and consummate the union. 
The future of stereophotogrammetry in biology and medicine lies in the 
hands of investigators, equipment manufacturers, and others in the 
biomedical and photogrammetric communities who are interested in 
devoting time and energy to sustained, well-conceived. research and 
development. The new insights which are likely to result from these 
undertakings have already been recognized by experienced observers as a 
worthy and exciting challenge——no less real, today. than when D'Arcy 
Thompson reported at the Royal Society of Edinburgh (1914-15 session): 
that: “In this paper I have dealt with plane coordinates only, and have 
made no mention of the more difficult subject of systems of coordinates 
in three-dimensional space. But if the difficulties of description and 
representation could be overcome, it is by means of such coordinates in 
space that we should at last obtain an adequate and satisfying picture of 
the processes of deformation and the direction of growth.” 
ACKNOWLEDGMENTS 
In the course of preparing this report many authors and other 
interested individuals, too numerous to mention individually, kindly 
responded to requests for reprints and reports; the National Aeronautics 
and Space Administration (Contracts NAS 9-10567 and NAS 9-11604) 
and Social Rehabilitation Service (16-P56813/6-10) provided necessary 
financial support, and my colleagues at the Texas Institute for 
Rehabilitation and Research and Baylor College of Medicine, Jaime 
Cuzzi, John Hugg and Ken Rouk, contributed valuable inputs and 
insights incorporated in the text. Finally, Miss Junille Wieting, Mrs. Marj. 
Gordon, and Mrs. Milli Wheatley diligently typed the manuscript and 
helped to collate the references. To all of these parties, I offer my 
sincere thanks. 
  
   
   
   
    
    
   
   
  
    
    
  
  
  
   
   
  
   
  
    
   
  
  
  
  
  
  
   
  
  
  
   
   
    
  
  
  
     
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