Modern Transmutation of the Elements 



203 



resolves itself suddenly into its constitu- 

 ent elements. It is true that here we have 

 a molecule composed of atoms "disin- 

 tegrating" into atoms which subsequently 

 combine to form new molecules of nitro- 

 gen and of chlorine; but in principle an 

 analogy may be drawn between the dis- 

 ruption of the molecules of an explosive 

 compound and the disintegration of an 

 atom into corpuscules. Professor Ruther- 

 ford and Mr Soddy showed, however, 

 that corpuscules which have been proved 

 by Professor J. J. Thomson, of Cam- 

 bridge, to be exceedingly minute are not 

 the only products of disintegration of 

 the radium atom ; the proof was adduced 

 that among these products were atoms of 

 a density comparable with that of hydro- 

 gen and helium. This hypothesis evi- 

 dently admitted of experimental proof, 

 and in conjunction with Mr Soddy I col- 

 lected the "emanation" or gas evolved 

 from salts of radium. We showed that 

 this gas, presumably of high density, dis- 

 integrates in its turn, and that perhaps 7 

 per cent of it changes into helium. What 

 becomes of the remaining 93 per cent is 

 as yet undecided; still, some hint may 

 be gained from the fact that a constant 

 ratio exists between the amount of helium 

 obtainable from a mineral and the weight 

 of lead which it contains. It may be that 

 lead forms the ultimate product, or at 

 least one of the ultimate products, of the 

 disintegration of the atom of emanation. 

 Another radioactive element, actinium, 



has been shown by its discoverer, De- 

 bierne, also to yield helium by the dis- 

 integration of the emanation or gas which 

 it continuously evolves. 



This disruptive change is attended by a 

 great evolution of heat ; for the radioctive 

 elements are in a sense explosive, and 

 explosions are always accompanied by a 

 rise of temperature. But such atomic ex- 

 plosions surpass in degree, to an almost 

 inconceivable extent, the molecular ex- 

 plosions with which we are familiar. 

 Could we induce a fragment of radium 

 to evolve all its energy at once, the result 

 would be terrific, for in the energy with 

 which it parts during its change it sur- 

 passes in explosive power our most po- 

 tent guncotton by millions of times. It 

 has been suggested that to this or similar 

 changes are due the continued high tem- 

 perature of the sun and the presence of 

 helium in its chromosphere. 



Up to the present no further cases of 

 transmutation have been observed than 

 those mentioned — radium and actinium 

 into their emanation, and these emana- 

 tions into helium. But proof is accumu- 

 lating that many forms of matter with 

 which we are familiar are also under- 

 going similar change, but at a vastly 

 slower rate. "The mills of God grind 

 slowly" — so slowly that many generations 

 of men must come and go before ocular 

 proof is obtained of the products of such 

 possible transmutations. 



BRAZIL AND PERU 



THE enthusiasm with which Brazil 

 and the other republics of South 

 America are preparing for the 

 Pan-American Congress at Rio de 

 Janeiro this summer well illustrates the 

 commercial prosperity and the political 

 permanence which practically the entire 

 continent is now enjoying. 



Brazil began the twentieth century 

 with 17,000,000 people, a territory larger 

 than that of the United , States, and un- 



developed resources surpassed by no 

 country with the possible exception of the 

 United States and China. Consul Seeger 

 writes as follows : 



Of all the South American countries 

 Brazil is the most extensive. It contains 

 an area of 3,200,000 square miles, is 

 2,630 miles long, 2,540 miles wide, and 

 has a population of 17,000,000, mostly of 

 Indian origin. It borders on every 

 country of South America except Chile. 



