vi PREFACE 



physics, photochemistry, certain biological products, zoology, and 

 botany. In short, the representatives of these fields served both as an 

 editorial board and as a publication committee (see list of editorial col- 

 laborators, page ii). It is obvious that those aspects of physical and 

 biological sciences embracing the relations of biological materials, physi- 

 ological processes, and the responses of organisms to radiation are far 

 too vast for detailed review in any single work. It is, however, indispens- 

 able to the effective work of the biologist that a careful selection of this 

 material should be so organized and presented that an adequately com- 

 prehensive view of the whole may be obtainable with a minimum of 

 time and labor. A complete bibliography alone would be an extensive 

 undertaking, and this could have none of the qualities of factual presenta- 

 tion, critical analysis, and systematization of method that are required 

 for better orientation of the research or teaching biologist, the interested 

 physicist or photochemist, and the qualified general reader. 



This Survey purposely excludes to a large extent practical considera- 

 tions relating to plant production. Likewise it excludes those phases of 

 applied radiology which are generally regarded as purely clinical or 

 therapeutic ; but at the same time it is recognized that clinical effects are 

 necessarily more clearly analyzed and interpreted through the avenue of 

 sound experimental findings, while the reasonableness of therapeutic 

 practice is logically based upon facts well estabhshed in the laboratory. 

 On the other hand, the applications in plant science, in medicine, and in 

 technology have, of course, notably stimulated research and enriched the 

 opportunities for fundamental work. Without extending too far the 

 limits of this work it was not possible to include chapters on applied 

 phases of absorption spectroscopy, emission spectral analyses of tissues, 

 and radiation problems relating to the phenomenon of vision in higher 

 animals and man. 



The publication of this book has been made possible by financial 

 support from the Committee on Radiation through contributions received 

 for the radiation program by the National Research Council from the 

 General Education Board, the Rockefeller Foundation, and the Common- 

 wealth Fund. The editor wishes particularly to express his thanks to 

 the collaborating editors — Drs. Cole and Failla, Daniels, Clark, Packard, 

 and Popp, representing the five primary fields of interest referred to 

 previously — for their indispensable and cooperative assistance. The 

 two-score of contributors — authors of the papers included — have earned 

 our gratitude not alone for their contributions but also for their sympa- 

 thetic consideration of details requisite for a certain harmonious treat- 

 ment of the whole. 



Madison, Wis., B. M. Duggar, Editor 



March, 1936. 



