Feb. 13, 1890] 



NATURE 



341 



studies through these reams and reams of paper. Con- 

 sequently, the first class of readers have hitherto for the 

 most part been satisfied to gain their knowledge of 

 Spencer through the " Cosmic Philosophy" of Fiske, 

 while the latter class have experienced a hitherto hopeless 

 difficulty in refreshing their memories upon particular 

 points, or in finding passages to which they may wish to 

 refer in publications of their own. Speaking for our- 

 selves, we are conscious of often having done a negative 

 injustice to Mr. Spencer on this account, simply because, 

 in order to avoid the possibility of any positive injustice 

 in the way of misrepresentation, we have deemed it wisest 

 not to allude to him at all. 



Now, the epitome which Mr. Howard Collins has 

 supplied so admirably satisfies all the requirements of 

 the case that henceforth the general reader will be able 

 to acquire a clear knowledge of Mr. Herbert Spencer's 

 philosophy in one-tenth of the time that it has hitherto 

 been necessary to expend, while — as Mr. Spencer himself 

 observes in his highly commendatory preface — more 

 serious students will find that " a clear preliminary con- 

 ception is more readily obtained from a small outline- 

 map than from a large one full of details." Lastly, for all 

 purposes of reference, this epitome leaves nothing to be 

 ■desired ; for not only does it run parallel with the original 

 — chapter by chapter and section by section — but it is also 

 furnished at the end with an alphabetical index of subject- 

 matter : so that, if a man is writing upon any of the in- 

 numerable topics which Mr. Spencer has handled, he 

 can immediately ascertain all that Mr. Spencer has said 

 with regard to them. 



For these reasons we cordially recommend this most 

 painstaking epitome to every class of readers ; and we 

 cannot doubt that its publication will greatly promote the 

 diffusion of Mr. Spencer's thought in all the English- 

 -speaking communities of the world. G. J. R. 



The Earth and its Story. Edited by Robert Brown, 



Ph.D., F.L.S. (London : Cassell and Co., 1889.) 

 The continued publication of good and popularly written 

 scientific works is one of the most gratifying signs of the 

 times ; it testifies, in no uncertain manner, to the growth of 

 a taste for scientific knowledge in the mind of the general 

 public, and hence is a matter of congratulation. 



Of all the sciences none may perhaps be made more 

 interesting than physical geography, or its modern 

 •equivalent physiography. The desire to know something 

 about the earth's position in the universe, its formation, 

 and its inhabitants, is and always has been innate in man, 

 and we are glad, therefore, to welcome works that may 

 satisfy this craving after light. The one before us deals 

 in a comprehensive manner with the geographical dis- 

 tribution of plants and animals, and the agents concerned 

 in their dispersion ; with the physics of the sea, waves, 

 currents, and tides ; with terrestrial magnetism ; climate 

 .and the causes affecting its distribution ; rainfall and 

 precipitation in general. A considerable amount of space 

 is given to descriptions of geological formations and the 

 fossils they contain, whilst ideal landscapes with restored 

 animals are plentifully figured. We regret, however, that 

 only a very meagre description is given of the earth as a 

 planet. It must be remembered that astronomy is a 

 very important part of physiography, even when looked at 

 from a utilitarian point of view. The reason why the 

 movements of the heavenly bodies have been studied 

 from time immemorial is that a knowledge of them 

 was necessary in order to meet the vicissitudes of life, and 

 even before primitive man had inquired into the constitu- 

 tion of the earth he had arrived at crude conceptions as 

 to the constitution of the universe from uncritical obser- 

 vations of celestial phenomena. The priority of these 

 conceptions demonstrates their importance, and therefore, 

 in a work intending to convey earth knowledge, the 

 verification of the earth's rotation and revolution and the 



determination of its true size and shape should certainly 

 be included. The measurements of arcs of meridian, 

 whereby the exact size and shape of the earth may be 

 found, are easy to describe, and preferable to the proofs of 

 the earth's rotundity known in the time of Peate ; be- 

 sides which, such investigations essentially belong to 

 physical geography. But, excepting these omissions, 

 the work is one of sterling value ; it is profusely illus- 

 trated, each of the two volumes containing twelve 

 coloured plates and about 270 woodcuts, and the explana- 

 tory text is very readable and interesting throughout. 

 Such a production will naturally gravitate to the free 

 public libraries and similar institutions, and will be of 

 great use in extending scientific knowledge. 



Steam. By William Ripper, Professor of Mechanical 

 Engineering in the Sheffield Technical School. 

 (London : Longmans, Green, and Co., 1889.) 



This volume consists of an elaboration of notes of 

 lectures given by the author to an evening class of young 

 mechanical engineers. For its size, it contains much 

 useful information ; and the simplicity of expression, and 

 the absence of elaborate calculation, throughout the 

 chapters help to make it suitable for elementary classes. 

 The author gives special prominence to the principles 

 involved in the economical use of steam. This part of 

 the book is particularly lucid and concise, being perfectly 

 clear to the average student. He also describes well the 

 compound, triple, and quadruple expansion engines, 

 especially dealing with the general idea of the expansion 

 and course of the steam through the cylinders on its way 

 to the condenser, as well as with the general laws regu- 

 lating the volumes of the cylinders. Although the 

 subject is treated in an elementary manner, there is much 

 sound work in the book. Text-books on steam have 

 greatly improved of late years from an engineer's point of 

 view, and the present volume is a good example of the 

 way in which the subject should be handled for the 

 benefit of budding engineers. 



The illustrations and diagrams are good, the former 

 being taken from engines in actual practice. Fig. 134, 

 however, does not represent particularly good practice. 

 The flat crown of the fire-box of locomotive type of 

 marine boilers is probably seldom stayed after the 

 manner shown ; the crown stays being generally screwed 

 through the shell of the boiler, and either rivetted over or 

 fastened with a nut and a copper washer. Assuming 

 that these stays are screwed through the fire-box crown 

 sheet, it would be interesting to know how the author 

 proposes to place them in position, as shown in the 

 figure. Fig. 137 represents a Ramsbottom locomotive 

 safety valve. Although correct in principle, it is quite a 

 curiosity in point of design, the valve in general use 

 being very different in appearance, as the reader may 

 observe by referring to the one shown on the locomotive 

 boiler illustrated in Fig. 132. We may say in conclusion 

 that a fuller index would have added considerably to the 

 value of the book. N. J. L. 



Australia Twice Traversed. By Ernest Giles. In Two 



Vols. (London : Sampson Low and Co., 1889.) 

 The narrative presented in these volumes has been com- 

 piled by Mr. Giles from the journals written by him during 

 five exploring expeditions into and through central South 

 Australia and Western Australia from 1872 to 1876. The 

 materials of the book are not, therefore, very fresh, but 

 this ought not to detract much from their interest, as 

 hitherto only fragmentary accounts of Mr. Giles's travels 

 have been printed. It must be admitted that records of 

 wanderings in the interior of Australia are not usually very 

 fascinating. Mr. Lumholtz's book, which we lately re- 

 viewed, is a brilliant exception to the general rule. We 

 cannot say that Mr. Giles's work rises to an equal height 

 above the ordinary level ; for it lacks that fine insight into 



