RADIUM.

Stratford Evening Post, Volume XXXVIII, Issue 99, 20 April 1914, Page 4

RADIUM.

The craze for radium as a cure foxcancer is now described as a “worldwide madness,” and tho price has accordingly risen to a prohibitive one. Radium is described as being diffusely distributed throughout the whole world

in quantities minute beyond imagiua-; tion. It is relatively concentrated in the ores, and the waters of an\ spas easily show its presence, but by I exact electrical methods , its activity ; is detected everywhere in the rocks, the earth, the sea, and iu the air. It, is a. metal belonging to the group; known as the alkaline earths. It is believed to be one of the three heav-j iest elements, coming after uranium and thorium. It forms salts which are chemically like those of other allied metals, and the bromide, chloride, sulphate, etc., have been produced in laboratories for some years. Owing to the rapidity with which it becomes oxidised in the air it was only in 1913 that the white unstable metal was successfully isolated in a pure condition. But the salts are sufficient for all practical purposes. The extraction from pitchblende is tedious and costly, for the proportion of radium is only one-part in five million. The ore is crushed, “roasted,” and the uranium removed by acids. Then after a series of treatments, there is left a solution which contains radium. Three processes of fractional crystallation are next performed, and the pure bromide or chloride is obtained at last. A ton of the best selected ore, treated with live tons of chemicals, yields a little over two grains of radium. The remarkable properties of radium in giving out rays and heat are found in all its salts; but are attributes of radium itself, and proportional to the amount of metallic radium!present. hi 1900 it was found that these salts when in solution produce an active gas or emanation. It was thought at the time that there was no alteration in weight, and it seemed impossible to explain the origin of the loss of energy. It has been proved, however that it takes about 2000 years j for radium to be reduced to half its I weight.