5i8 



NA TURE 



[September 20, 1906 



is iffiiored that radio-activity is, to use Mme. Curie's 

 liappy expression, an atomic property, that is, is in- 

 dependent of the particular state of chemical com- 

 bination of the radio-element. Radium resembles in 

 the closest possible manner barium, a completely 

 inactive element in the same family of the periodic 

 table, both in chemical nature and in the series 

 relationships of its spectrum. Barium is an element, 

 radium is a compound ; but whether uranium and 

 thorium are elements or compounds is undecided. 

 Again, the emission of energy, greater a million-fold 

 than that evolved in any previous material change, 

 remains a mystery in company with the discrepancy 

 between the physical and geological estimates of the 

 age of the earth. The constancy of ratio between the 

 quantities of radium and uranium in all natural 

 minerals is another experimental fact unexplained. 



It is the glory of the accepted view that it 

 harmonises and correlates all the preceding problems, 

 offering a simple and unstrained physical explanation 

 of each, capable of being tested by quantitative ex- 

 periment. In addition, it reaches out in every direc- 

 tion in broad, bold predictions, a few of which, like 

 the production of helium from radium and the con- 

 stancy of ratio between uranium and radium in 

 minerals, have been brilliantly confirmed bv experi- 

 ment, while the majority simply await more refined 

 experimental methods of attack. Of what other 

 theory could the remark be made, which is attributed 

 to Prof. Rutherford, that when a single experimental 

 fact is established which does not conform to the 

 disintegration theory it will be time to abandon it? 

 Tlie theory would have to be fundamental indeed to 

 pass this test. 



The secret of the vague hostility to the new doc- 

 trines which the recent controversy has shown to be 

 widely felt is to be found probably in the impossi- 

 bility of forming from words or reading the least 

 idea of the really startling character of some of the 

 new discoveries. This is particularlv true of perhaps 

 the most wonderful of them all, the radium eman- 

 ation. Even Lord Kelvin in one of his letters speaks 

 vaguely of emanations, while Sir William Crookes, 

 at least until quite recently, employed the word, also 

 in the plural, as a generic term "for the radiations. 

 Give a scientific man a few milligrams of radium in 

 solution and ask him to perform for himself some 

 of the stock experiments with the emanation, for 

 example, its condensation by liquid air, the concentra- 

 tion on the negative electrode of the active deposit 

 formed by it, the steady decay of its powers after re- 

 moval from the radium, and the growth of new eman- 

 ation by the radium, kept, let us say, in another build- 

 ing or another country; then the 'radium emanation 

 passes from being a phrase to a fact which no theory 

 can _ safely ignore. The same is equally true of 

 thorium X, radium C. and the numerous other suc- 

 eessive products of radio-active change. 



It would be a pity if the public \vere misled into 

 supposing that those who have not worked with 

 radio-active bodies are as entitled to as weighty an 

 opinion as those who have. The latter are talking of 

 facts they know, the former frequently of terms they 

 have read of. If, as a result of the recent controversy, 

 it has been made clear that atomic disintegration is 

 based on experimental evidence, which even its most 

 hostile opponents are unable to shake or explain in 

 any other way, the best ends of science will have 

 been served The sooner this is understood the better, 

 for in radio-activity we have but a foretaste of a 

 fountain of new knowledge, destined to overflow the 

 boundaries of science and to impregnate with teeming 

 thought many a high and arid plateau of philosophy. 



F. SoDDY. 

 NO. 1925, VOL. 74] 



THE MYSTERIES OF LHASA.' 



THIS is a new and cheaper edition of Colonel 

 Waddell's account of our recent expedition into 

 Tibet. In its more expensive shape it passed through 

 two editions, and the present one is a marvel of 

 cheapness. Not very many of the illustrations in the 

 issue of last year are omitted in this year's reprint, 

 and the type is the same, so much so, indeed, that 

 it has not been considered necessary to remove from 

 the letterpress references to photographs that have not 

 been reproduced (see, for instance, pp. 369, 374, 406, 

 and 411). It is not often that one can buy a hand- 

 somely printed book of 550 pages, with more than 

 150 illustrations, eight excellent maps and plans, and 

 a very good index for a few shillings. 



One of the most alluring things about the book is 

 its title. The contents bear out this title only to a 

 limited extent. It is true that we have here a descrip- 

 tion of Lhasa and its sights of much the same kind 

 as a guide-book would give of a European city and 

 its sights ; but not much of this is very new. We 

 have had descriptions, and even photographs, of 

 Lhasa and its palaces before. What people mean 

 when they speak of the mysteries of the place may 

 include this, but it refers in the main to something 

 very different. The author is well aware of this. He 

 refers in his preface to the curiosity stimulated by 

 the belief that somewhere behind the mighty Kan- 

 chenjunga there would be found a key to unlock the 

 mysteries of the world ; and the belief in the possi- 

 bility of this is widely diffused. 



The ball was set rolling, though this is not gener- 

 ally known, by the famous Earl of Chesterfield, the 

 author of the well-known letters to his son. This 

 was done in another work of his entitled " The 

 Economy of Human Life," published in 1751. Un- 

 willing at that date to give his views of life and 

 religion under his own name, he wrote anonymously; 

 and the method he adopted was to prefix to his book 

 an elaborate introduction, in which he describes Lhasa, 

 its palaces and its libraries, tells us how the Emperor 

 of China, fully convinced that there could be found 

 in those libraries ancient books of wisdom, sent a 

 learned minister, "of a grave and noble aspect," and 

 armed with an autograph letter from the Emperor to 

 the Grand Lama, to discover them ; tells us further 

 how the minister found many " curious pieces of 

 antiquity," and how the most ancient of them all 

 was precisely the original of this " Economy of 

 Human Life"; and finally explains the very curious 

 ways in which this ancient MS. was translated, and 

 then sent to him, who now gives it to the world. It 

 is all very well done — as romance ; but it was taken in 

 sober earnest. The book went through more than fifty 

 editions, and has been often translated. No one 

 seems to have divined, until last year, that it was 

 merely an English book of the eighteenth century. 

 The editor of the last English edition {1902) still 

 speaks of it as " this ancient wisdom "; and its great 

 success led to no less famous imitations purporting 

 to be the work of the so-called Mahatmas of Tibet. 

 On these interesting delusions the author merely 

 states that inquiries of learned Tibetans he happened 

 to meet with, and such cursory examination as was 

 possible of the libraries passed on the road, led to no 

 result. Such negative evidence is not of much value. 

 He might have added that the mystery is not in Tibet 

 at all, but in certain phases of European thought. 



In this connection it is noteworthy that Colonel 



1 " Lhasa and its Mysteries, with a Record of the Expedition of igo3-4." 

 By L. A. Waddell, LL.D., C.B,, Lieut..CoI. Indian Medical Service. 

 Third Edition. Pp. xx + sso. (London : Melhuen and Co., 1906.) Price 



