December, 1903.] 



KNOWLEDGE. 



283 



English and several other languages. A description of the 

 species, a statement of its range, and an account of its habits, 

 follow in concise form. The book should be e.xceedingly useful 

 to the traveller, provided he bears in mind that very many 

 distinct geographical forms have been entirely omitted. 



"Agricultural Geology.'' By J. B. Marr, ma., f.r.s. 

 Pp. xii. + 320. (Methuen.; 6s. Illustrated. — This book is 

 written to suit the requirements of candidates for the Inter- 

 national Diploma of Agriculture. It suffers to a certain extent 

 from the apologies which its author so frequently makes for 

 passing over interesting and even important portions of his 

 subject. Either so admirable a teacher of geology should not 

 undertake to write a text-book which cannot appeal to him as 

 a work of art, or he should imbue himself with the peculiar 

 needs of his readers, and give the book the appearance of a 

 continuous narrative, which shall captivate the student, and 

 entrap him towards something higher. No two writers will 

 agree precisely as to what shall be omitted in the " acting 

 version " whicih they place before the public. We, for instance, 

 should have laid stress on the iron-ores as ingredients of soils 

 (p. IW), seeing that the muddy streamlet and the warm brown 

 new-ploughed land alike owe their colour to limonite, and 

 ultimately to magnetite, and ferriferous silicates, a fact well 

 recognised on p. 88. We should have omitted mention of nitre 

 (p. 33), used mainly for gunpowder, but should have given the 

 precise chemical composition of Kainite and Carnallite, and have 

 explained why this is not realised in commercial samples (pp. 

 33 and 309). The origin of these salts forms one of the most 

 fascinating chapters in geology ; and agricultural students are 

 not the mere " practical " persons referred to on p. 307. They 

 are unwittingly concerned with the most poetic and natural of 

 all professions ; and the geologist may be proud to meet them 

 on the question of the regeneration of the earth. We admire 

 Mr. Marr's clear treatment of denudation, and of the resulting 

 surface-features (pp. 81-134). Here the agricultural require- 

 ments in soils are stated in a very concise form, the author 

 evidently desiring to avoid overlapping on other branches of 

 the curriculum. His use of "lime," however, for "carbonate 

 of lime," is too great a concession to agricultural custom (p. 96). 

 Still more excellent is the section on geological surveying (pp. 

 143-210), which will make the published maps appeal in all their 

 detail to the reader. The concluding chapters on stratigraphical 

 geology are inevitable, owing to the requirements of examiners; 

 but they naturally cballenge comoari.son with many ordinary 

 te-xt-books of geology. We confess that we should like to see 

 the physical part of the book expanded, and the pupil left to 

 study in detail the country in which he proposes to found his 

 home. The British Isles, by which public examiners mean 

 England and a part of Wales, have too long been made a fetish ; 

 aud students will rattle off the succession of Jurassic strata near 

 Lackhamptou who have no conception of some of the most 

 important epochs in the evolutionary history of the globe. 

 Mr. Marr must have felt himself again and again hampered in 

 the preparation of the present treatise, which does not rival 

 those well-known books in which he struck across new country. 



"Mo.-;tlv MAM.MALS." By R. Lydekker. 383 pp. 1903. 

 (Hutchinson & Co.) — This is a volume of collected essays, which 

 " have previously appeared in periodical literature ; the great 

 majority in Knowi.udge, but others in Xnttire, the Field, and 

 the A!ii<in." Save in a few instances only, these essays are 

 iiresented in their original form or "with such alterations as 

 have been found necessary in order to bring them up to date, 

 and with a few omissions to avoid unnecessary repetition. A 

 certain amount of repetition will, indeed, still be found to exist, 

 as somewhat similar ground is, in certain instances, traversed in 

 the course of two separate articles. To have avoided this would 

 have entailed practically re- writing some, or the total omission 

 of others." We cannot but regret that this plan of issue was 

 decided upon, since some of the articles would most certainly 

 have been improved by re-casting and addition. Nowhere is 

 this more noticeable than in the chapter on '' .Vnimals Exter- 

 minated during the Nineteenth Century," which occupies rather 

 loss than seven pages. Again, the chapters on " The Coloration 

 of Large Animals,"' and "Spots and Stripes in Mammals," would 

 undoubtedly, if re-cast and made to form a -single essay, have 

 gained in value. It is scarcely necessary, in the pages of 

 Knowledge, to indicate further the nature of the contents 

 of this book and, doubtless, the intrinsic merit of those articles 



which have appeared in this journal will induce the readers 

 thereof to buy the volume for the sake of the essays which have 

 appeared elsewhere. 



" A Naturalist's Calendar, kept at Swaffham Bulbeck, 

 Ca.mbridgesiure, by Leonard Blomefield (formerly 

 Jenyns)." Edited by Francis Darwin. Pp. xviii. -\- 84. 

 (Cambridge University Press.)— Mr. Blomefield was an accurate 

 and painstaking naturalist, whose nature calendar was founded 

 on observations made near Cambridge between the years 1820 

 and 1831. Every Cambridgeshire naturalist will be glad to 

 possess a copy of this calendar, which shows the average date of 

 appearance and of various stages of development of plants and 

 animals, and the earliest and latest occurrence of each pheno- 

 menon. Mr. Darwin, in an appreciative introduction, points 

 out that Mr. Blomefield was known for his minute and 

 scrupulous exactness in matters of fact, so that his record is of 

 real scientific value, as weU as being of interest to the amateur 

 naturalist. By means of the calendar and its index it is easy to 

 find the mean, earliest and latest dates on which birds appear, 

 commence and cease to sing ; when the leaves of plants are seen 

 and flowers open and fruit appear; as well as of many other 

 phenological phenomena. The common as well as the scientific 

 names are given, jto that the calendar can be consulted and under- 

 stood by anyone interested in outdoor life. The dates only apply, 

 of course, to the Cambridge district, and very decided differences 

 will be noticed by naturaUsts in other places. Our field clubs 

 should always keep in mind that they cannot perform a more 

 useful and appropriate work than that of preparing and 

 publishing such records. 



" Smithsonian Physical Tables." Prepared by Prof. 

 Thomas Gray. Second Revised Edition. Pp. xxxiv. -\- 301. 

 (Washington : Smithsonian Institution.)— The publication of 

 tables of trustworthy results in physics, meteorology and 

 geography, is one of the many ways in which the Smithsonian 

 Institution assists scientific progress. To the student of science 

 and to the investigator it is very convenient to be able to refer 

 readily to the values obtained by well-known authorities, whose 

 methods of experiment and careful work give reason for con- 

 fidence in their results. In the volume before us tabulated 

 values are given for practically every physical constant or 

 relation, with references in most cases to the publication from 

 which the results have been obtained. Mathematical tables are 

 also included, and the whole is weU indexed. Separate volumes 

 are ijublished for geographical and meteorological data, but 

 revised editions of these have not been published for some years. 

 It would be an advantage if revised editions, in which new 

 results are included, could be published every year or so. 



"The Cloud World: its Features and Significance." 

 By Samuel Barber. Pp. vii. -i- 139. (London : Elliot Stock.) 

 Illustrated. 7s. (Id.— The value of this book lies in the original 

 observations it contains, and in the excellent illustrations, many 

 of which have already appeared in the pages of Knowledge. 

 IMr. Barber is an enthusiastic student of clouds and related 

 phenomena, and his volume directs attention not only to their 

 beauty of form, but also to their relation to weather. He states 

 his observations as matters of fact, and in most coses is conteot 

 to leave their theoretical significance out of consideration. 

 Years of study have enabled Mr. Barber to know " the 

 balancing of the clouds," and to read forthcoming weather 

 from the signs of the sky. He recognises that many cloud 

 phenomena are local ; nevertheless, the results of his studies 

 are applicable to any part of the British Isles, and can be consulted 

 profitably by all who wish to nnderstand the messages c;irried 

 by clouds of various tyi)es. Sun pillars, waterspouts, colour of 

 sky, and auroral displays are among other subjects described, 

 mostly from the author's own experiences. Finally, there is a 

 descriptive list of clouds of many kiuds, with fine pictures 

 reproduced from |)hotograi)hs, so that anyone who cares to take 

 up the study of clouds will find the book both inspiring aud 

 instructive. 



'■Limanora: The Island op Progress." By Godfrey 

 Sweven. ^Putnams. 190:i.) 6s.— An Utopian romance that is 

 founded on science to an extent unapproached by any of its 

 jiredeces-sors in that department claims notice in a scientific 

 periodical. This novel with a Maori-sounding name is, perhaps, 

 the first of its kind to bo saturated with the idea of evolution 

 and all its kindred conceptions. A mere enumeration of the new 

 scientific ideas which its author's keen curiosity and adventurous 



