Nov. 24, 1887] 



NATURE 



75 



from the perfection of our means of research, we are 

 apt to lose in independence and vigour of mind, to say 

 nothing of the time which is wasted in the weary wading 

 through piles of periodicals, often with but little fruit as 

 the result. Mathematicians know that solving problems 

 gives a strength to the mind which cannot be obtained 

 from the most careful study of book-work, and I have 

 often ventured to think that to write the section on the 

 " literature of the subject " as the last stage of a research 

 is not so much to "• put the cart before the horse " as it 

 seems. Something, too, may be lost through the very 

 perfection of the means of research in natural history : the 

 mind may be tempted to dwell too much on details ; and 

 the over-careful study of these may lead men to miss the 

 greater principles. Darwin was an observer, precise and 

 minute as any, but it is interesting to note that he was 

 always guided by a selective principle. 



The greatest charm of the " Life " is that it draws so 

 vivid a picture of the man himself — partly from the un- 

 conscious self-portraiture of his letters, partly from the 

 tender touch of his son's hand, aided by the loving 

 memories of other members of his family. Before us 

 rises that tall, slightly stooping form, either walking with 

 swinging though often feeble step, cloaked and staff in 

 hand, along the " sand walk," or seated or reclining in 

 that study which bore silent testimony to the orderly habits 

 learnt in the tiny cabin of the Beagle ; we see that massive 

 forehead, those keen yet kindly eyes, shadowed by those 

 overhanging brows, the sparse gray hair, the long gray 

 beard, that winning smile which lit up those rugged 

 features ; we hear once more the kindly voice ; but better 

 still, there rises, fresh and ever instructive, the memory 

 not only of one of the grandest intellects, but also of one 

 of the noblest and truest natures, among the sons of men. 

 Unruffled by carping criticism and virulent abuse, in 

 silent dignity Charles Darwin laboured on, in the quiet 

 consciousness of strength and the conviction that truth 

 would at last prevail. No one can read the life of 

 Darwin without feeling as if some healthful air from a 

 better world had braced his moral fibre and nerved him 

 for more earnest and more unselfish work. 



Truly the last scene of all was a " Great Lesson." His 

 family would have laid him in the quiet churchyard near 

 his own home; but his fellow-workers in science desired 

 md obtained that his grave should be made in West- 

 minster Abbey. Some quarter of a century before that 

 day many thoughtful men hesitated in accepting, or even 

 opposed, the views which he had maintained ; while the 

 camp-followers and swash-bucklers of the religious world 

 had discharged at him their volleys of vituperation. The 

 one had been for the most part persuaded ; the other had 

 slunk away to growl in obscurity. Now, around that 

 grave in the Valhalla of Britain, were gathered the leaders 

 in literature and science, men of every rank in life, of 

 every form of creed — from the most sincere Christian to 

 the no less sincere Agnostic. Time had shown that there 

 was no necessary opposition between the inductions of 

 science and those deeper aspirations and beliefs upon 

 which we must not here touch, and men who on such 

 points felt deeply but differently from Charles Darwin 

 came no less willingly than others to pay the last honours 

 to one who was not only a great philosopher but also 

 emphatically a good man. T. G. Bonney. 



OUR BOOK SHELF. 

 A Treafise on the Integral Calculus. Part L Containing 

 an Elementary Account of Elliptic Integrals and Appli- 

 cations to Plane Curves, with numerous Examples. By 

 Ralph A. Roberts, M.A. (Dublin: Hodges, 1887.) 



Most students, on taking up this book, will be disposed 

 to ask, " Is there any room or necessity for another 

 work on the Calculus just now? Is not Williamson 

 up to date ? " Mr. Roberts gives no sign, and so 

 we are led to search out for ourselves a reason for the 

 existence of the work, and a justification of the same. 

 In his two previous books our author makes great use of 

 elliptic functions, and a chapter is devoted to the discus- 

 sion of them in the book before us, and, further, this fact 

 is prominently noted on the title-page ; hence we conclude 

 that Mr. Roberts has had in view mainly the treatment of 

 these integrals, and to make his treatise self-sufficient 

 he has surrounded this special subject with such preli- 

 minaries and accessories as he deems suitable for the 

 elucidation of his theme. The author has produced a 

 capital book, for he writes with extreme care, and full 

 knowledge and command of his subject. There appears 

 to us to be in many parts a novel treatment — i.e. con- 

 sidering the matter in the light of English treatises on 

 the Calculus— and there is copious illustration. There is 

 large opportunity for practice afforded by the numerous 

 examples inserted in the body of the work, and also at 

 the end. Many of these are not intended, or at any rate 

 are not suitable, for babes ; they are strong meat for adults. 

 There is an index and the usual table of contents. 



Solutiofis to Problems contained in a Tt-eatise on Plane 

 I Co-ordinate Geometry. By I. Todhunter, F.R.S. Edited 



by C. W. Bourne, M.A. (London : Macmillan and 



Co., 1887.) 

 This is not a work brought out with a rush, for the greater 

 portion of the solutions were drawn up by the author 

 fifteen years ago. To students using the text-book this 

 will be a valuable companion, for Mr. Bourne has 

 executed his task with care and ability. Geometrical 

 as well as analytical solutions are given, and impart a 

 pleasant feature to the book. For Mr. Bourne's sake we 

 regret that the foundation is giving way, as few students 

 now read the " Conies," for that fate is befalling it which 

 the author himself says is " the fate of all academical 

 text-books," viz. obscurity ("W. Whewell," vol. i. p. 24). 

 Todhunter's own views respecting " Printed Solutions " 

 are given in his " Essays" (p. 81). The exercises, how- 

 ever, will retain their utility as tests for ascertaining a 

 pupil's grasp of the subject, in spite of the decay of the 

 setting, and the "Solutions" we can recommend to 

 students " after a vigorous effort has been made to obtain 

 the solution without the book." 



Lectures on Bacteria. By A. De Bary. Second Improved 

 Edition. Authorized Translation by Henry E. F. 

 Garnsey. Revised by I. B. Balfour, F.R.S. (Oxford : 

 Clarendon Press, 1887.) 

 This work is in the main an abridgment of a number of 

 lectures, some of which were delivered in a connected 

 series as a University course, others as occasional and 

 separate addresses. The author's aim is to set forth 

 the present state of our knowledge respecting the objects 

 included under the name of Bacteria. Having dealt \yith 

 cell-forms, cell-unions, and cell-groupings, he describes 

 the course of development of Bacteria, and then proceeds 

 to discuss questions as to the position of Bacteria in the 

 organic world, and as to their origin and distribution. A 

 chapter on vegetative processes is followed by one on the 

 relation of liacteria to, and their effect upon, their sub- 

 stratum ; and this leads to an account of the forms which 

 excite fermentation, and of parasitic Bacteria. The remain- 

 ing chapters are on the harmless parasites of wann- 

 blooded aaimals, on anthrax and fowl-cholera, on the 



