28 



NA TURE 



[November 9, 189; 



source of the iron is to be found in volcanic emanations 

 of ferric chloride, a theory that appears more ingenious 

 than sound. The author does not appear to have con- 

 sulted the writings of recent foreign workers in this field. 

 A study of the memoirs of R. D. Irving, Kimball, 

 Van Hise, and H. V. Winchell, on the genesis of 

 American iron ores, might have induced him to modify 

 some of his views. 



The author's remarks on the value of geology to the 

 mining engineer deserve attention. It is undoubtedly 

 of urgent importance for the economical utilisation of 

 the iron ore resources of the kingdom, that those entrusted 

 with the management of mines should have a more ex- 

 tended knowledge of the nature of irregular deposits 

 than is too often the case. In these days of technical 

 education, it is surprising to see money wasted in search- 

 ing for these deposits in situations where some know- 

 ledge of stratigraphy would have shown that there was 

 no chance of finding them. It is surely not too much to 

 ask that mineral explorers should understand the 

 elements of their work. Bennett H. Brough. 



OUR BOOK SHELF. 



The Shrubs of North-Eastern America. By Charles S. 

 Newhall. 8vo, pp. 249, with 116 woodcut figures. 

 (London : G. P. Putnam's Sons, 1893.) 



The author of the present volume had previously written 

 a similar book on the trees of the same region, which he 

 defines as " Canada and the United States east of the 

 ]Mississippi and north of the latitude of Southern Penn- 

 sylvania.'' This region is peculiarly rich in both trees 

 and shrubs, most of which are hardy and will flourish 

 in this country ; and, as a matter of fact, many are 

 familiar here in cultivation. Therefore a work of this 

 kind appeals to amateurs on this side of the Atlantic as 

 well as the other, and, although an unpretentious produc- 

 tion, we can recommend it as a useful aid to those 

 interested in the subject, especially to such as already 

 possess some general knowledge of shrubs. The de- 

 scriptive part is as free from technicalities as it could well 

 be, and intelligible to any person whose knowledge of 

 botany does not go beyond the veriest rudiments. The 

 figures are for the greater part merely outlines, and so 

 far accurate ; yet hardly sufficiently detailed for use in 

 our gardens, where American plants are associated with 

 those of all other temperate climes. In the fields and 

 forests of America they would be more serviceable. 

 Botanical and popular names are given, and the deriva- 

 tion of the former, at least as to genera. The descriptive 

 matter is here and there enlivened by appropriate 

 poetical quotations ; and the properties and uses of the 

 more important plants are given. The Ericaceae are 

 perhaps the most numerous and attractive among the 

 shrubs of Eastern America. No fewer than ten genera 

 of this family are enumerated. Missing the Rose Acacia, 

 Rohinia hispida, we had almost convicted the author of 

 omitting a favourite shrub ; but we find it does not reach 

 quite so high a latitude as 40^ in America, though it is 

 quite hardy in most parts of the British Islands. We also 

 missed \^& Menispcrniuin, Wistaria, and other climbers ; 

 but we suppose they will be included in the " Vines" of 

 North America, to be dealt with in a third volume, 

 announced by the author. W. B. H. • 



Meitsiiratioti of the Simpler Figures. (Univ. Corr. 



Tutorial Series.) By William Briggs and T. W. 



Edmondson. (London: Clive Univ. Coll. Press, 1893.) 

 Those students who have acquired a fair knowledge 

 of algebra, trigonometry, and Euclid, will find in this 



NO. 1254, VOL. 49] 



book a most excellent guide to the mensuration of 

 most of the more simple figures generally met with. 

 Instead of presenting the reader with the stereotyped 

 " rule and example " system, the authors have treated 

 them as just a series of problems giving proofs of the 

 formulae used and numerous examples. That the book 

 throughout is clearly and yet not too fully written speaks 

 well for the student, and its scope is intended to meet 

 the requirements of candidates for such examinations as. 

 the Intermediate B.A. and B.Sc. of the University of 

 London. The measurement of rectilinear figures and 

 the circle are first treated, followed by chapters on the 

 geometry of the rectilinear solids and their surface- 

 areas. This is succeeded by the methods of measuring 

 the volumes of the rectilinear solids, and the last two 

 chapters deal conclusively with the cylinder and cone 

 and the sphere. The definitions throughout are well 

 expressed, and the problems neatly worked out, while 

 the figures could hardly be improved. We may mention 

 that in the chapters relating to the rectilinear solids all 

 figures have been drawn in perspective and shaded, 

 giving the student a clearer idea of the forms of the 

 various figures. 



The Discovery of Australia. By Albert F. Calvert 

 (London : George Philip and Son, 1893.) 



Mr. Calvert describes his book as " a simple state- 

 ment of such historical facts as I could collect ; and a 

 reproduction of certain maps which more or less illus- 

 trate the gradual progress of knowledge regarding the 

 great island continent, now called Australia." From this 

 it will be inferred that there is nothing strikingly novel 

 in the production. Mr. Calvert has found many tracings 

 on old charts indicating a knowledge of the existence of 

 a great southern continent, and he thinks that probably 

 some individual navigator landed on the western coast 

 of Australia in the fifteenth or sixteenth century, after- 

 wards bringing the news of his discovery to Europe. A 

 large portion of the book is devoted to the voyages of 

 Capt. Cook, the reason being that " he was really the 

 discoverer of Australia in its present geographical con- 

 figuration." The volume is well printed, and the maps 

 are finely reproduced. It is doubtful, however, whether 

 the author has added much to elucidate the subject 

 which he treats. 



Graphic Arithmetic and Statics. By J, J. Prince. 

 (London: Thomas Murby, 1893.) 



In addition to questions in Practical Geometry, the 

 Science and Art Department has given notice that 

 in the future questions in Graphic Arithmetic and 

 Statics will be included. The issue of this small book 

 is intended to supply students with information on these 

 two subjects, sufficient for both the elementary and 

 advanced stages. In forty-eight pages the author has 

 brought together all the important problems, working 

 them out clearly for beginners with the help of diagrams. 

 In addition to those of the more elementary kind, a 

 graphical determination of the square roots of numbers, 

 the resolution of forces, resultant of parallel forces, iS:c., 

 are also dealt with. Nothing that the reader will find in 

 this book will be found superfluous, though it could with 

 advantage be slightly extended. 



The Crchid Seekers. By Ashmore Russan and Frederick 

 Boyle. (London: Chapman and Hall, 1893.) 



Up the Sarawak river to Kuching, and thence to Siram- 

 bau, went a small party in search of a blue orchid re- 

 ported to exist in that region, and supposed to he Vanda 

 ccerulea or V. carulescetis. The leader of the party was 

 a German botanist well versed in orchidology, who iden- 

 tified each plant as it was found, and delivered botanical 

 discourses whenever an opportunity occurred. The story 



