122 



NA TURE 



[December 3, 1908 



are mutually convertible, for the appearance of elec- 

 tricity represents a corresponding disappearance of 

 matter. The theories of the indestrucnbility of matter 

 and energy are overthrown. All matter and energy 

 are disappearing from the universe to be ultimately 

 converted into aether. 



The second half of the book contains an account 

 of experiments, with numerous illustrations by the 

 author in support of his views. Some simple elec- 

 trostatic experiments are described from which he 

 draws truly astonishing conclusions. The latter part 

 of the book is devoted to. a description of his experi- 

 ments on phosphorescence and " black light." This 

 portion of the book will be found very instructive to 

 those w^ho are interested in the little-known subject 

 of phosphorescence. \ number of striking- experi- 

 ments are described, and the author has obviouslv 

 taken great trouble to make the results as conclusive 

 as possible. The general idea is that phosphorescence 

 is a result of the transformation of atoms of matter. 

 There still remains much to be done in this field of 

 inquiry, but it has not yet been proved that the 

 molecular combinations and dissociations under the 

 influence of light are not sufficient explanation without 

 having recourse to the transformation of atoms. 



The book is full of trenchant criticisms, and neither 

 principles nor theories are spared which do not fall 

 in with the author's views. We gather, \yhether 

 rightly or wrongly, that the author has little respect 

 for the orthodox man of science, whom, apparently, 

 lie considers is steeped in formuke and filled with 

 conservatism, but yet not so conservative that he is 

 not capable of taking the excellent views of Le Bon 

 without giving credit for them. We are familiar with 

 examples of our non-mathematical scientific brethren 

 who abhor the sight of a simple equation. M. Le 

 Bon is evidently of their opinion, as may be seen 

 from the following quotation, which also serves as 

 an example of his vigorous style :— 



" What has finally given very great force to certain 

 principles of physics and mechanics has been the very 

 complicated mathematical apparatus in which they 

 have been wrapped. Everything presented in an alge'- 

 braical form at once acquires for certain minds The 

 character of indisputable truth. The most perfect 

 sceptic willingly attributes a mysterious virtue to equa- 

 tions and bows to their supposed power. They tend 

 more and more to replace, in teaching, reason and 

 experience. _ These delusive veils which now surround 

 the most simple principles onlv too often serve to 

 mark uncertainties. It is by lifting them that I have 

 succeeded more than once in showing the frailty of 

 scientific beliefs which for many scholars possess' the 

 authority of revealed dogmas." 



Assuming the correctness of the hypotheses and 

 statements of the author, the book forms interesting 

 reading, and is full of original ideas. It is a different 

 matter when one proceeds to examine the evidence 

 in favour of his theory. Men of science are very 

 chary, and rightly so, of hypotheses reared on a very 

 slender foundation of fact which endeavour to ac- 

 count for the universe and all that it contains. Some 

 experimental proof is required before such hv.^otheses 

 are seriously entertained. It is true that the study 

 of the radio-active bodies has led to the belief that the 

 NO. 2040, VOL. 79] 



atoms of active matter undergo spontaneous trans- 

 formation and are the seat of a large store of 

 energy. iMany are prepared to believe that the same 

 is true of the atoms of ordinary matter. Experi- 

 ment seemed at first to indicate that all matter was 

 radio-active, and was in a state of slow trans- 

 formation. Recent work, however, has cast grave 

 doubt on this conclusion, for it is fairly certain that 

 the greater part of the apparent activity of ordinary 

 matter, with the exception, possibly, of potassium and 

 its salts, can be explained without the necessity of 

 assuming that the atoms of ordinary matter are dis- 

 integrating. The study of the internal heat of the 

 earth shows that if ordinary matter is evolving energy 

 due to atomic transformation, it must do so at a 

 rate very small compai-ed with even a weakly radio- 

 active substance like uranium. As Strutt has pointed 

 out, the internal heat of the earth would be much 

 greater than it is if ordinary matter disintegrated 

 at even one-thousandth the rate of uranium. It is 

 probable that the transformation of the atoms c f 

 matter may be much accelerated under the inllu- 

 ence of exceedingly high temperature and its accom- 

 panying manifestations. It seems to have been over- 

 looked that Sir Norman Lockyer long ago advanced 

 this idea from a study of the constitution of the stars. 

 The astronomical evidence in support of the view 

 that the atoms of matter undergo transformation is 

 collected in liis interesting book, " Inorganic Evolu- 

 tion." 



One of the main hypotheses of Le Bon is that elec- 

 tricity is derived from the decomposition of atoms of 

 matter. On this view, the electricity which passes 

 through a copper wire is derived at the expense of 

 the copper, and ultimately the latter will vanish into 

 a quantity of intangible aether. On account of the 

 great store of electricity in an atom of matter, this 

 disappearance will take place ver}- slowly. It is nnw 

 generally believed that the passage of electricity 

 through a conductor is due to the transference of 

 charged carriers, but it is exceedingly doubtful whether 

 there is any loss of matter in the process. There 

 is so far not the slightest experimental evidence in 

 favour of the assumption. 



The book is clearly written, and the interest is 

 maintained throughout. W'e can recommend it to 

 readers who are interested in revolutionary ideas of 

 physics and in the spectacle of the debacle (according to 

 Le Bon) of a large amount of scientific doctrine. We 

 would suggest, however, that the reader need be under 

 no obligation to consider the statements contained in 

 it as the latest accepted scientific gospel. 



BIOGRAPHY OF SPENCER. 

 The Life and Letters of Herbert Silencer. By Dr. 

 David Duncan. Pp. xi + 621; with seventeen illus- 

 trations. (London : Methuen and Co., n.d.) Price 



IT is not long since we had Mr. Herbert Spencer's 

 voluminous "Autobiography," and now we have 

 his " Life and Letters " — a labour of love executed 

 with marked success by Dr. David Duncan, who was 

 for a time the philosopher's secretary and collabo- 



