VI - PREFACE 



but not to a close, among other things, the controversial subject of maximum 

 efficiency. 



This arrangement left out many not unimportant "miscellaneous" 

 topics, such as the more recent work on photosynthesizing and chemo- 

 synthesizing bacteria, photochemical nitrate metabolism, etc. The mono- 

 graph as a whole therefore does not quite live up to the ambitious stand- 

 ard of coverage set in the first volume. 



No attempt has been made to treat the problems of large-scale culturing 

 of microscopic algae for food (and other practical purposes), to which so 

 much public attention has been drawn lately. Reference must be made in 

 this connection to the symposium "Algal Culture, from Laboratory to 

 Pilot Plant," edited by J. S. Burlew, and published by the Carnegie Insti- 

 tution of Washington in 1953 (Publication No. 600), which contains con- 

 tributions by leading investigators in this field. ^ 



Each of the three volumes — 1, 11,1 and 11,2 — contains an Author Index 

 of the Main Investigations. A Subject Index was provided in Volume I, 

 but not in 11,1 ; the present Volume 11,2 contains a comprehensive Subject 

 Index for all three volumes. 



If the writing of this monograph were to be started now, a somewhat 

 different plan would have been adopted, with a different distribution of 

 emphasis. Some chapters now resemble a scaffolding, erected years ago, 

 behind which no building has appeared, and which one would now be in- 

 clined — perhaps too hastily — to dismantle. There is, however, relatively 

 little material, even in the earliest chapters, which does not contribute to 

 the establishing of a proper perspective in the whole field. The poUcy — 

 adopted at the beginning of the work — of discussing all alternatives and 

 suggestions, has paid off in leaving the author free of commitment to any 

 by now flagrantly obsolete theory. In fact, systematic reading— which 

 is more than can be expected for a monograph of this bulk — would re- 

 veal that many of the current "new" ideas in photosynthesis have been 

 proposed or discussed somewhere in it. 



At the end of the book (p. 1994) the author expresses hope that it will 

 not rapidly become obsolete, even if the rate at which new developments 

 follow in the field makes it inevitable that it will be incomplete already at 

 the date of its publication. Some of the developments of the years 1954-55 

 could at least be mentioned in the "Epilogue" (Chapter 38); others were 

 published (or came to the author's attention) too late for this purpose. 



The electron microscopic study of the chloroplast structure has entered 

 a promising new stage with the improvement of techniques for the preserva- 



1 More recent summaries, presented at the Phoenix, Arizona, Conference on Applied 

 Solar Energy (Oct. 30-Nov. 4, 1955) will be published in the proceedings of this con- 

 ference. 



