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Prolog 



ue 



Nearly sixty years ago, Emil Fischer described his experi- 

 ments which led to the discovery of the structure of glucose 

 and related sugars. In the past fifteen years Melvin Calvin 

 and his associates have performed experiments leading to an 

 understanding of the reactions used by photosynthetic organ- 

 isms to make these sugars and many other compounds from 

 carbon dioxide, water, and minerals, using the energy of light. 



It was not long after the basic reaction of photosynthesis 

 was recognized that speculation regarding its mechanism com- 

 menced. These discussions were carried forward first by Justus 

 von Liebig and then by Adolf von Baeyer and, finally, by 

 Richard Wilstatter and Arthur Stoll, into this century. How- 

 ever, it was the mechanism of the reverse pathway, that is, 

 the combustion of carbohydrate to carbon dioxide and water 

 with the utilization of the energy, which was first successfully 

 mapped. This pathway was elucidated primarily by Otto 

 Meyerhof and Hans Krebs. 



Professor Calvin's interest in the basic process of solar 

 energy conversion by green plants began about 1935, when he 

 was studying with Professor Michael Polyani at Manchester, 

 There he became interested in the remarkable properties of 



