NA TURE 



241 



THURSDAY, JULY 13, 1905 



THE POPLLARISATIO.X OF SCIEXCE. 

 The New Knoivledge. By Robert Kennedy Duncan, 

 Professor of Chemistry in Washington and Jeffer- 

 son College. Pp. xviii + 263. (London: Hodder 

 and Stoughton, 1905.) 



THE author of this attempt to make the progress 

 of recent discovery in chemistry and physics 

 understanded of the people remarks in his preface : — 



" The great expositors are dead, Huxley and 

 Tyndall and all the others ; and the great expositor 

 of the future, the interpreter of knowledge to the 

 people, has yet to be born." 



.\nd (but it must be added quite modestly) he 

 attempts to wear the cloak of the prophet. He is 

 right, on the whole, when he says that " the pro- 

 gressive teacher, particularly in the high school or 

 smaller college, finds it often exceedingly difficult to 

 gain access to the original sources of knowledge," 

 and, it may also be remarked, to understand them 

 when he does. Hence any serious attempt made by 

 one sufficiently versed in science to avoid error, and 

 with sufficient appreciation of the difficulties of one 

 who has not made science his speciality to know how- 

 to present facts and their interpretation, is deserving 

 of a cordial welcome. Indeed, most scientific men 

 are in the position of outsiders towards sciences not 

 their own ; and an allusion to the recent effort made 

 by the Chemical Society to present the year's progress 

 to their Fellows is here not inappropriate, for to such 

 an extent is specialisation now carried that it is prac- 

 tically impossible for the physical chemist to follow 

 the researches of the organic chemist, and vice versd. 

 Their " Annual Reports on the Progress of Chemistry 

 for 1904 " will be much appreciated by all chemists. 

 It is true that the organic chemist, for example, may 

 consider the amount of space devoted to his branch 

 insufficient, and the treatment of the subject-matter 

 somewhat scrappy ; yet to one \\ ho has no time to 

 follow in detail the work of the specialists published 

 ■ in numerous journals during the year, a summary 

 like this is of the greatest value. It is very desirable, 

 in subdivisions of a science, as well as in separate 

 sciences, that the bearing of one branch of knowledge 

 on another should be realised, and so far understood; 

 and the Chemical Society is to be congratulated on 

 its new effort. It is to be hoped that a similar plan 

 will be adopted by physiologists, geologists, and, 

 indeed, by all those who labour for the " promotion 

 of natural knowledge." 



But to return to Prof. Duncan's book. Beginning 

 with the " three entities," matter, ether, and energy, 

 an attempt is made in seven pages to give the reader 

 some idea that these are the conceptions in terms of 

 which the modern man of science interprets nature. 

 The doctrines of the conservation of mass and of 

 energy, and the necessity for the assumption of the 

 existence of ether are indicated. I doubt whether an 

 entire outsider would gain much by reading this 

 chapter; still, if it stimulates him to think, and to 

 NO. 1803, VOL. 72J 



try to acquire clearer ideas on the subject, much will 

 have been accomplished. We have then certain 

 elementarv conceptions of chemistry expounded, 

 molecules, atoms, compounds, and elements, and so 

 closes part i., which consists of eleven pages. 



To give the reader an idea of the author's style, a 

 quotation from the first paragraphs of part ii. may 

 be made. 



" We believe — we must believe, in this day — that 

 everything in God's universe of worlds and stars is 

 made of atoms, in quantities x, y or c respectively. 

 Men and women, mice and elephants, the red belts 

 of Jupiter and the rings of Saturn are one and all 

 but ever shifting, ever varying, swarms of atoms. 

 Everv mechanical work of air, earth, fire and water, 

 every criminal act, every human deed of love or valor : 

 what is it all, pray, but the relation of one swarm of 

 atoms to another? 



" Here, for example, is a swarm of atoms, vibra- 

 ting, scintillant, martial, — they call it a soldier, — and, 

 anon, some thousands of miles aw-ay upon the South 

 .\frican veldt, that swarm dissolves, — dissolves, for- 

 sooth, because of another little swarm, — they call it 

 lead. 



" What a phantasmagoric dance it is, this dance 

 of atoms ! And what a task for the Master of the 

 Ceremonies. For mark you the mutabilities of 

 things. These same atoms, maybe, or others like 

 them, come together again, vibrating, clustering, 

 interlocking, combining, and there results a woman, 

 a flower, a blackbird or a locust, as the case may be. 

 But to-morrow again the dance is ended and the 

 atoms are far awav ; some of them are in the fever 

 germs that broke up the dance, others are ' the green 

 hair of the grave,' and others are blown about the 

 antipodes on the winds of ocean. The mutabilities of 

 things, and likewise the tears of things : for one 

 thing after another, 



* Like sno\v upon the Desert's dusty Face 

 Lighting a little hour or two — is gone,' 



and the eternal, ever-changing dance goes on." 



Now this purports to be very fine writing, but does 

 it gild the pill of science? I am inclined to think 

 not. .Still, tastes may differ. 



It would be unfair to judge of the book, however, 

 by this quotation. The subsequent sections deal with 

 the periodic classification, gaseous ions, corpuscles, 

 and here a very lucid account is given of the method 

 of estimating the velocity of a corpuscle, and of the 

 relation of the charge to the mass ; really in these 

 sections the author has established his character as 

 a clear expositor. Positive ions are then considered, 

 and then natural radio-activity, in which there is a 

 capital sketch of the discovery of radium and of its 

 properties. A subsequent chapter treats of thorium, 

 uranium, radium, and actinium, with the reproduction 

 of Prof. Rutherford's latest results, and the section 

 concludes with the radio-activity of substances in 

 general. The next " part " deals with the resolution 

 of the atom and with atomic disintegration, and an 

 intelligible account is given of Prof. J. J. Thomson's 

 most recent work. The heat-emitting property of 

 radium is next dealt with, and then there is a sum- 

 mary of the " electrical nature of matter." The book 

 concludes with part v., entitled " Inorganic Evolu- 

 tion and Inorganic Devolution," discussing intelli- 

 gently and intelligibly Sir Xorman Lockver's theories 



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