WONDERFUL RADIUM.

Huntly Press and District Gazette, Volume XXII, 5 August 1932, Page 1

WONDERFUL RADIUM.

HOW IT WAS DISCOVERED (By A.K.M., in Melbourne Age.) Shortly after Rontgen discovered the X-rays emitted from a discharge tube (which during the emission, fluoresced) it occurred to Becquerel that the phenomenon might be reversible—if X-rays cause materials to fluoresce or phosphorese, will the reverse hold, and will a fluorescent or

phosphorescent body be found to emit penetrating rays? In the pursuit of such inquiry Besquerel tried the effect of certain substances, notably uranium salts, on photographic plates wrapped in several thicknesses of paper. In some cases he obtained positive results, and the radiation was known as Becquerel rays. In reality it had not its source in the phosphorescence of uranium or other salt; and in this respect Becquerel’s idea was erroneous. The work which followed on his discovery soon showed that the radiation from pitchblende—an ore from which uranium is obtained—was much more intense than that of pure uranium salts. This set the Curies on their quest for the substance responsible for this intense radiation, and, after very patient and very brilliant work, they succeeded in isolating a new element, radium, and opened up the field of radio activity, the study of which has developed in such a remarkable manner. The birth of this subject thus took place in the erroneous idea of Becquerel’s mind; and another striking fact is that precisely the same result as Becquerel obtained in his experiments had been obtained some 30 years previously by Victor de la Nie- | pee; but the Curies necessary for its development were not then on the spot to develop the full results of the discovery, and so it was for the time ' forgotten. Some idea of the magnificence of the work of the Curies is gathered from the fact that they succeeded in isolating radium from pitchblende, although there is only about one-hun-dredth part of an ounce of it per ton of the ore. Their work was only possible on account of the discovery of the gold leaf electroscope, for the ordinary methods of chemical analysis are incapable of dealing with minute quantities of this order; and 30 years previously at the time of Niepee’s discovery, such methods only were available.