336 



DISCOVERY 



in California and ^Mexico experienced similar misfortune. 

 One party located in Central IMexico was more successful 

 and was able to observe a portion of the total phase. 



Hector Macpherson. 



Reviews of Books 



Botany. A Junior Book for Schools. By R. H. Yapp, 

 M.A. (Cantab.), Mason Professor of Botany in the 

 University of Birmingham. (Cambridge University 

 Press, 35. (td.) 



All who are interested in the teaching of Botany to 

 beginners should make a point of securing a copy of this 

 excellent book. It is admirably suited to the purpose 

 for which it was A\Titten ; in particular the clear and 

 careful original drawings, and the well-thought-out 

 scheme of practical work, deserve mention. The standard 

 is that of the Junior Local Examination of the University 

 of Cambridge. R. J. Y. P. 



Essays of a Biologist. By Julian Huxley. (Chatto & 

 Windus, 75. 6d.) 



ifr. Julian Huxley is not only the inheritor of a famous 

 name ; he also possesses gifts of style and skill in pre- 

 sentation of his arguments that were the hall-mark of 

 his famous ancestor. He has a deep interest in the border- 

 lands of science and philosophy, biology and theologv 

 \\ hich were always fascinating his grandfather and brought 

 him into sharp contact with leaders of thought in his daj-. 

 Discovery cannot follow the author into his discussions 

 with theologians who have much to say on the conclu- 

 sions he has reached. There is less misunderstanding 

 nowadays than there was half a century ago, and it is 

 well to have laid down clearly that a " law of nature is 

 not something revealed, not something absolute, not 

 something imposed on phenomena from without or from 

 above ; it is no more and no less than a summing up, in 

 generalised form, of our own observations of phenomena : 

 it is an epitome of fact, from which we can draw general 

 conclusions." Our "laws of nature" are entirely 

 dependent on our knowledge of the facts of nature, and 

 we can claim no finality for these laws. Conclusions 

 dra-i\'n from laws have in their last resort to appeal to 

 facts to verify them. Science, when it goes beyond facts 

 and deals with processes and ultimates, has to call in the 

 aid of philosophy and theology, and we excuse ourseh'es 

 from dealing here with the great questions that are raised 

 by our author in his concluding Essays. They have their 

 weight coming from a man who has carefully studied the 

 subject, but they are by no means universally accepted 

 by scientists. Theologians reject them even when they 

 are men of scientific attainments, and philosophers are 

 not of one mind on them. 



In his Essay on Progress Mr. Huxley breaks a lance 

 with Inge and Bury, who deny the existence of a law of 

 progress. We think that they are not so much in disagree- 

 ment as may appear. Has the mind of man in historic 

 times increased its capacity to achieve more with the 

 material at hand than in the past ? ^^'e have seen the 

 Golden Age of Athens and its fruits have never been sur- 



passed, and the fact that man has capabilities greater 

 than those beings lower in scale of evolution does not 

 imply that man possesses the further capability of pro- 

 gress which would prove the contention of our author. 

 Here we have to make the usual induction of facts from 

 which a law of progress has to be deduced, and it is at 

 least an open- cjuestion whether Inge and Bury are not 

 as right in their view as Mr. Huxley believes himself to 

 be in his. Closely connected with this Essay is the 

 following paper on Biology and Sociology, in which he 

 shows not onh- the difference but the natural connection 

 between pure biology and sociology. Man is capable of 

 ideas and of transmitting his ideas to such an extent that 

 " the experience of Moses, Archimedes, or Charlemagne, 

 of Jesus, Newton, or James Watt is modifying our 

 behaviour to-day." 



The paper on Bird Mind is fascinating and attractive. 

 Mr. Huxley acutely observes and as delightfully describes 

 his observations. The pages describing the courtship of 

 the Grebes may be placed, without suffering in com- 

 parison, by the side of Maeterlinck's famous passages on 

 the Bees, and here we have Mr. Huxley at his best. Sex 

 Biology and Psychology contains sound criticism on many 

 current theories, and we are glad to read his protest 

 against the indiscriminate use of psycho-analysis. 

 Philosophic Ants bases a series of reflections on the Ant- 

 republic under the influence of heat. We have already 

 referred to the concluding papers, which are Rationalism 

 and the Idea of God and Religion and Science : Old Wine 

 ill Neiv Bottles, and we take leave of a suggestive and 

 informing volume by quoting its closing words : " That 

 moulding of matter by spirit is, under one aspect. Science ; 

 imder another. Art ; under still another, Religion. Let 

 us be careful not to allow the moulding forces to counter- 

 act each other when they might co-operate." To do this 

 it is necessary to understand the limitations of Science, 

 Art, and Religion. T. J. Pulvertaft. 



Practical Plant Ecology. A Guide for Beginners in the 

 Field Study of Plant Communities. Bv A. G. Tansley, 

 M.A., F.R.S. (7s. 6d.) 

 This book is intended " as a guide for those who are 

 attracted to ecological work, but are imcertain as to how 

 to set about it." The study of plants and animals as they 

 exist in their natural homes or, as the author happily 

 puts it, the investigation of their household affairs — that is 

 what Ecology means — is a branch of biology which has 

 made rapid progress in recent years, and many botanists 

 have devoted themselves to this difficult and fascinating 

 pursuit. One difficulty has been the lack of a satisfactory 

 guide. Formerly botanical excursions were mainly 

 devoted to collecting and naming plants and searching 

 for new localities : we have now gone beyond that stage. 

 Ecology does not supplant systematic botany ; a basis 

 of sound systematic knowledge is essential ; but the 

 ecologist must also be a plant physiologist. His aim 

 is to learn as much as possible about the actual life of a 

 plant, why it grows in one place and not in another, why 

 certain plants usually grow together ; in short, he sets 

 himself the task of going to the root of the matter, not 



