RADIO-ACTIVE SODIUM

Evening Star, Issue 21994, 2 April 1935, Page 9

RADIO-ACTIVE SODIUM

PROPERTIES AND POSSIBILITIES DISCUSSION BY DR G. G. FARR The discovery of radio-active sodium, referred to by Dr J. D. Crockroft at the’ conference of the Institute of Physics, was discussed yesterday by Dr C. C. Farr, professor of physics at Canterbury College, in an interview following the publication of the cable message. “Madame Curie’s daughter married a scientist named Joliot,” said Dr Farr, “ ami together they have been carrying on the work of Madame Curie and her husband in Pan's. Lately they have been ‘ bombarding ’ various elements with various ‘ bomhai-ders ’ —of which a number are now available—the alpha and beta, particles of radio-activity, protons, and neutrons. “ When ordinary elements, other than radium, are ‘ bombarded,’ radioactivity can bo induced. Sodium becomes unstable and excited, as anyone might if bullets were flying round him. The sodium takes some time to settle down and in the meantime radio-active properties are exhibited. Rays of different sorts, like those of radium, are given off. “We might compare the agitation of the sodium in its loss by bombardment with that, which would ensue in the British Empire if a part of it—say New Zealand—were suddenly knocked off. The Empire would bo thrown into a state of agitation, and it would take some time for it to settle down into a stable Empire again. In the case of radium the ejected part becomes a helium atom. In that of radio-active sodium it might he of another element. “ The radio-activity induced in sodium lasts only a very short time compared with that of radium. Dr Crockroft says that if the discovery is developed radio-active sodium may take the place of radium. _ But this shortness of the radio-active period is an important drawback, although the activity is intense while it lasts. The period taken for tho emanation of rays to he reduced to half is only a few da vs.”

Dr Farr added that Dr Crockroft had done much work with Lord Rutherford.