1 1 2 RADIOBIOLOGY 



G. Evelyn Hutchinson 

 Radioactive Carbon 



Reprinted with the permission of publishers 

 from the American Scientist 39:473-476, 

 1951. 



Twenty years ago, the suggestion the phenomenon was widespread, the 

 that pieces of charcoal could bear their result of our search will be reason- 

 own date lines and belemnites their ably well-founded scientific knowledge; 

 temperature charts, would have ap- where it was localized, however intense 

 peared preposterous, yet most of the the local impact, the search will almost 

 present notes are to be devoted to sober always remain historical speculation, 

 investigations showing indeed that this But, to distinguish is not to condemn, 

 is the case. Vet)' simply and obviously, As long as the human mind is free, it 

 the answer is that if a past event has will speculate, and there is always a 

 left some trace over a very wide area or chance, even if remote, that something 

 \olume, we may hope ultimately to will turn up and that the speculative 

 find that trace, however small, simply result will be confirmed and emerge as 

 by improving our technique. This is firmly established histor}', 

 what Libby and Urey have done in the 



work to be discussed below. If the carbon 



event, however important its conse- 

 quences might be in later times, was of The perfection of the radiocarbon 



a strictly local character, unless it be- method of dating carbonaceous ma- 



longcd to histon,' recorded at the time, terials, elaborated bv W. F. Libbv, has 



the odds are against us, whether we are been widelv and justifiablv regarded as 



searching for the first bird or the Holy one of the most remarkable scientific 



Grail. Such a distinction obviouslv in- achievements of the past decade, 

 volvcs considerations not unlike the The full series of dates available up 



capacity factors and intensity factors to September 1950 has been printed in 



of the physicist and engineer. Where a pamphlet distributed to interested in- 



