no POPULAR SCIENCE MONTHLY 



men were carried away by the strangeness of the new phenomena and 

 were ready to adopt the most extravagant theories when there was no 

 logical necessity for abandoning old views and, in their intoxication, 

 were embracing new hypotheses without exercising due circumspection. 

 After the meeting Lord Kelvin boldly opened a controversy in the 

 London Times. Almost single-handed the old warrior fought with 

 great intellectual keenness against the transmutational and evolutionary 

 doctrines, relating to the chemical elements, framed by the younger 

 investigators, to account for the properties of radium. 44 Among his 

 opponents were Sir Oliver Lodge, the Hon. Mr. Strutt, Mr. A. S. 

 Eve and Mr. F. Soddy. It can not be said that Kelvin was victorious, 

 but the controversy helped to define the points at issue. Among other 

 things, Lord Kelvin said that there was no experimental foundation 

 for the assertion that the heat of the sun was probably due to radium. 

 He was still inclined to ascribe it to gravitation. Lord Kelvin also 

 denied that it was proved that the heat of the earth is due to radium. 

 It was possible, he claimed, that radium does not decompose under the 

 conditions prevailing in the interior of the earth, and in that case it 

 emits no heat. 



In considering the perturbations produced by radium in the prog- 

 ress of our ideas, it is well to remember that, thus far, we have been 

 able to experiment with radium in only small amounts. Professor 

 Lankester remarks that the Curies never had enough of radium chlo- 

 ride to venture on any attempt to prepare pure metallic radium. 



Altogether the Curies did not have more than some four or five grains of 

 chloride of radium to experiment with, and the total amount prepared and now 

 (1906) in the hands of scientific men in various parts of the world probahly 

 does not amount to more than 60 grains at most. When Professor Curie lec- 

 tured on radium four years ago at the Royal Institution in London he made 

 use of a small tube an inch long and of one-eighth inch bore, containing nearly 

 the whole of his precious store, wrenched by such determined labour and con- 

 summate skill from tons of black shapeless pitch-blende. On his return to 

 Paris he was one day demonstrating in his lecture room with this precious tube 

 the properties of radium when it slipped from his hands, broke, and scattered 

 far and wide the most precious and magical powder ever dreamed of by al- 

 chemist or artist of romance. Every scrap of dust was immediately and care- 

 fully collected, dissolved, and re-crystallised, and the disaster averted with 

 a loss of but one minute fraction of the invaluable product. 45 



In a reinvestigation of the age of the earth it is extremely impor- 

 tant to undertake extensive investigation of the amount of radium 

 contained in the various rocks. Such researches have been begun by 

 the Hon. E. J. Strutt. He has made determination of the amount 

 of radium in rocks at the surface of the earth, and has found about 



"See Nature, Vol. 74, 1906, pp. 516-518. 

 46 Nature, Vol. 74, 1906, p. 323. 



