150 ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 45 



possible to detect neutrons several miles away. The war has inter- 

 rupted much of the peacetime research of the medical cyclotron, but 

 a remark by Prof. Sir J. J. Thompson, of Cambridge, at Winnipeg 

 shortly after the discovery of radium applies equally well to the prod- 

 ucts of the cyclotron : "It is imperative, lest we should be passing over a 

 means of saving life and health, that the subject should be investi- 

 gated in a much more systematic and extensive manner than there 

 has yet been either time or material for" (18). 



Looking down on the Berkeley campus of the University of Cali- 

 fornia, said to be the largest educational center in the world, across 

 the great expanse of San Francisco Bay, with its artificial island of 

 400 acres and with two of the greatest bridges in the world, the scene 

 is now dominated by the vast circular observatory-like building, 165 

 feet in diameter and 90 feet high, erected on a hilltop to house the 

 latest cyclotron. As we think of the human activity behind all this 

 achievement the motto on the California State Capitol seems peculiarly 

 appropriate — "Bring me men to match my mountains." 



ACKNOWLEDGMENTS 



It is a pleasure to acknowledge here the many kindnesses shown me 

 by Prof. E. O. Lawrence, Dr. J. H. Lawrence, and the staff of the 

 .Radiation Laboratory at the University of California, Berkeley; I 

 am also grateful to them for permission to use illustrative material 

 from published papers. 



1. (a) Waite, A. E. Hermetic and alchemical writings of Paracelsus. Elliott 



and Co., London, 1894. 

 (6) Stoddabt, A. M. Life of Paracelsus. Rider and Son, London, 1915. 



2. Becquerel, H. Compt. Rend. Acad. Sci., vol. 122, pp. 420, 501, 559, 689, 762, 



and 1086 ; vol. 123, p. 855, 1896. 



3. Curie, P., Mme. P., and Bemont, G. Compt. Rend. Acad. Sci., vol. 127, 



p. 1215, 1898. 



4. Rutherford, E., Chadwick, J., and Eleib, C. D. Radiations from radioactive 



substances, pp. 7, 283-284. University Press, Cambridge, 1930. 



5. Editorial, Radiography, vol. 3, p. 133, 1937. 



6. Curie, Eve. Madame Curie (translated by Vincent Sheean), p. 204. Heine- 



mann Ltd., London, 1938. 



7. Blackett, P. M. S. Proc. Roy. Soc, vol. A 107, p. 349, 1925. 



8. Joliot, F., and Curie, I. Nature, vol. 133, p. 201, 1934. 



9. (a) Lawrence, E. O., and Livingston, M. S. Phys. Rev., vol. 40, p. 19, 1932 ; 



vol. 45, p. 608, 1934. 



(5) Lawrence, E. O., and Cooksey, D. Phys. Rev., vol. 50, p. 1131, 1936. 

 (c) Lawrence, E. O., et al. Phys. Rev., vol. 56, p. 124, 1939. 



10. (a) Hodges, F. J. Radiography, vol. 39, p. 440, 1942. 



(6) Kerst, D. W. Nature, vol. 157, p. 90, 1946. 



11. Editorial, Radiography, vol. 6, p. 93, 1940. 



12. Kubie, F. N. D. Gen. Electr. Rev., June 1937, p. 264. 



