January 29, 1903] 



NA TURE 



2 9. 



revision (to our mind abundantly justified) of Herbert 

 Spencer and Bain's theory of " overproduced move- 

 ments " in mental ontogeny ; and especially, perhaps, in 

 the tracing of his own theory of knowledge to its out- 

 come in the doctrine of "genetic modes," he often uses a 

 notation which to biologists as such may seem somewhat 

 unfamiliar. No one, however, who is at the pains to 

 follow him through his chains of argument, often intricate, 

 but with few exceptions consistent and intelligible, will be 

 inclined to deny the great service he has done in submit- 

 ting the problem of organic development to philosophical 

 analysis. 



It will be satisfactory to those biologists who still re- 

 gard Darwin and Wallace as the true founders of a 

 rational theory of evolution that the author, in demon- 

 strating the inadequacy and improbability of use- 

 inheritance, and in rightly laying stress on the importance 

 of individual adjustment and of social transmission, does 

 most explicitly assert the dominance of natural selection. 

 '• The value of accommodation," he allows, "is implicit 

 in the theory of natural selection," and in more than one 

 place (as in chapter xii., with its comprehensive table of 

 the various kinds of " selection ") he expresses his con- 

 currence with Prof. Poulton's statements to the same 

 effect. There is thus no room to doubt of his attitude 

 towards the general question ; but it is somewhat sur- 

 prising, and, we think, regrettable, that in the case of the 

 "highest and most specialised form of accommodation," 

 viz., the intelligence, Prof. Baldwin speaks of the re- 

 sulting "emancipation from the operation of natural 

 selection and from dependence upon variations " in a 

 way that seems open to misconstruction. There can be 

 no such emancipation in the long run. Naturam expelles 

 furca, tamen usque recurret. Whatever allowance we 

 make for individual adjustment to environment, whether 

 it be intelligent or not, there will be no reason to say 

 that "the struggle for existence is in some degree done 

 away with " unless we limit our outlook to variations 

 other than variations in plasticity. It is true that 

 the struggle is transferred " in some degree ' to 

 the sphere of the latter, but the " direct action 

 of natural selection " is not thereby evaded. All 

 individuals but a few (comparatively) are still eliminated 

 in virtue of the same failure of correspondence with the 

 environment ; only this failure is, or may be, in the indi- 

 vidual's power of accommodation, not in his invariable 

 or fixed endowment. If, on the other hand, we were to 

 hold, as Prof. Osborn seems to do, that this plasticity is 

 an inherent power or function of protoplasm undirected 

 and uncontrolled by natutal selection, we should, of 

 course, find ample reason for Prof. Baldwin's expres- 

 sions. But he makes it elsewhere perfectly clear that 

 he differs on this point from Prof. Osborn, and we there- 

 fore think that he would do well on a future occasion to 

 avoid the appearance of putting plasticity, in its relation 

 to selection, on a footing distinct from that of other 

 qualities. It would be hard to show that any character- 

 istic property of protoplasm did not take its share in the 

 "fundamental endowment of life" and was not " part of 

 its final mystery." Where, then, is the justification for 

 claiming an exemption for one property which is not 

 claimed for all ? 



We should have much more to say, did space permit, 

 NO. 1735, VOL. 67] 



in commendation of this excellent and stimulating book. 

 Many of the points raised are enticing subjects for dis- 

 cussion, but those features that call for adverse criticism 

 are few in number and of little importance. The plan of 

 the work, several chapters of which have already appeared 

 under other conditions, necessarily involves a certain 

 want of system and concentration ; nor must the reader 

 expect to find all that deals with one part of the subject 

 gathered into one place. On the other hand, the author 

 is enabled to enforce his arguments by repetition, and, as a 

 sentence in his preface reminds us, "to the psychologist, 

 at least, repetition has its pedagogical justification." 



F. A. D. 



A HISTORY OF AERONAUTICS. 

 Travels in Space. By E. Seton Valentine and F. L. 

 Tomlinson. With an Introduction by Sir Hiram S. 

 Maxim. Pp. 32S ; with about sixty illustrations. 

 (London : Hurst and Blackett, 1902.) 



IT appears to be a growing practice in this country to 

 publish books with a preface by some man of dis- 

 tinction, whose name figures prominently on the cover. 

 It is a pity that publishers cannot agree to discountenance 

 this practice. Either a book is worth reading without 

 the recommendation or it is not worth reading even with 

 it. Not but what the introduction in this case is worth 

 reading. 



The task which Messrs. Valentine and Tomlinson have 

 had before them has been no easy one. They have no 

 doubt derived considerable help from the French 

 " Histoire des Ballons" and other books of a similar 

 character, but even with that help they must have had to 

 wade through a large mass of literature and then to sum 

 up the principal points in a very short compass, all of 

 which takes much time. The authors are greatly to be 

 congratulated on the success with which they have com- 

 pleted their undertaking. The designs of Leonardo da 

 Vinci, the fantastic project of Lourenco, the abortive 

 attempts at flight by Besnier and De Bacqueville, the 

 balloon ascents of Montgolfier, Pilatre de Rozier 

 Blanchard, Nadar, the impossible air-ships of Petin and 

 De Landelle, the actual glides of Lilienthal, Pilcher, 

 Chanute, Santos Dumont rounding the Eiffel Tower, the 

 Pax disaster, all these give a very inadequate idea of the 

 large number of designs, projects, ascents, descents, 

 successes, failures and fatalities described in these pages. 

 There are few people so well versed in the history of 

 aerial navigation that they would not learn something 

 new and interesting on reading the present volume. 



The authors confine themselves to the task of 

 chronicling and describing, and do not indulge in lengthy 

 speculations as to the future of the flight-problem. 

 Seeing how uncertain that future is, they have acted 

 wisely. At the same time, Sir Hiram Maxim points out 

 that the book may have a useful purpose in the near 

 future in preventing others from repeating experiments 

 that have previously been tried and failed. The list of 

 aeronauts who have met their death as the result of their 

 aerial experiences since 1783 should be a warning to 

 future experimenters or would-be experimenters. Theo- 

 retical considerations, numerical calculations and mathe- 

 matical formula: lie outside the scope of this book. 



