VI 



PREFACE 



Dr. Ellsworth C. Dougherty in Part III, is in the form of a survey of those 

 isotopes which have already been used and those which, because of their 

 convenient physical properties and biological significance, may reasonably 

 be employed in future research. No effort has been made to present an 

 exhaustive and detailed account of the biological and medical research since 

 several excellent reviews have already been published, particularly those of 

 Hevesy, Kamen, and Lawrence and Hamilton. 



The need for a book covering the fields of tracer methods and nuclear 

 radiations, sufficiently technical to be of use in the laboratory, was early 

 recognized by Col. A. P. Gagge of the Aeromedical Laboratory at Wright 

 Field, Ohio. It was at his suggestion and with the enthusiastic support of 

 Dr. John H. Lawrence that initial preparation of the present volume was 

 undertaken. The first draft, written for the Army Air Forces, was com- 

 pleted in November, 1947, and printed shortly afterward in a limited edition 

 which appeared as A. F. Technical Report No. 5669. Despite the great 

 numbers of errors and omissions, there seemed sufficient interest in this 

 report to justify a comprehensive revision. The original manuscript, conse- 

 quently, was completely rewritten and extended in scope for the present 

 edition. 



Much of the credit for the existence of the book must be given Colonel 

 Gagge and the Army Air Forces, for whose early interest and support we are 

 fully appreciative. From its beginning through to completion, preparation 

 of the book has had the active interest and indispensable support of Dr. 

 Lawrence, to whom the authors owe a great debt of gratitude. 



The chapters submitted by the contributing authors, Drs. Ellsworth C. 

 Dougherty, Cornelius A. Tobias, James S. Robertson, Rayburn W. Dunn, 

 and Patricia P. Weymouth, have greatly extended the scope and usefulness 

 of the book. Without their assistance it is doubtful that, even if completed, 

 the book would have served a useful function. We wish especially to thank 

 Dr. Dougherty for the time and effort required for his preparation of the 

 entire biological section of the book, Part III. In addition to the authors 

 cited above we wish to thank Dr. R. L. Dobson for preparing Sec. 19.2 and 

 Dr. M. C. Fishier who began the initial compilation of the bibliography of 

 isotope literature. To aid in identification, the name of each author has 

 been placed at the head of the chapter he submitted. We wish also to 

 acknowledge our indebtedness to Drs. G. T. Seaborg and I. Perlman for 

 permission to use their table of isotopes, to Dr. R. Serber for permission 

 to include the range-energy data calculated by Walter Aron and B. G. 

 Hoffman of the Radiation Laboratory ©f the University of California, and 

 to the authors and publishers who readily gave permission to reprint many 

 of the graphs and tables. 



A considerable portion of the labor in preparing the manuscript was borne 



