32 



KNOWLEDGE. 



January, 1913 



wisely availed himself of the assistance of specialists in the 

 different subjects, while at the same time keeping the general 

 style and arrangement the same throughout the book. 



In the case of each industry there is not only a clear 

 description of the manufacturing processes with illustrations 

 of modern apparatus, but outlines are also given of methods 

 suggested by recent patents. Full references to the scientific 

 literature are also placed under each section, so that the book 

 must prove of great assistance to the manufacturers, patent 

 agents, and students engaged in industrial research, as well as 

 being of interest to the general reader. We notice that in the 

 section upon vinegar, the editor acknowledges his indebted- 

 ness to an article that appeared in "Knowledge" as the 

 source of his most recent information. 



It is perhaps invidious to single out any particular sections, 

 but the chapter on Synthetic Rubber, by Dr. Martin, and that 

 on the manufacture of Synthetic and other Drugs, by Dr. 

 Challenger, deserve mention as being particularly good. In 

 some of the sections however, there are indications that the 

 writer has a general rather than a special knowledge of his 

 subject, although for the reason mentioned above this was 

 probably inevitable. 



It is surprising how few organic industries have escaped 

 notice, as the present reviewer has found by test references 

 to the excellent index. The manufacture and valuation of 

 artificial organic manures, however, ought certainly to 

 find a place in a treatise of this kind, and the modern pro- 

 cesses of treating roads for the prevention of dust, with their 

 advantages and drawbacks would form another useful section. 

 Considering the enormous amount of matter in the book the 

 misprints are very few, and are mainly slips of a single letter. 

 "Zoological" for " zoogloeal " however, on page 316, is an 

 amusing example of a printer's interpretation of a word that 



was new to him. „ ... 



C. A. M. 



A Second Year Course of Organic Chemistry for Tech- 

 nical Institutes. — By F. B. Thole, B.Sc. (Lond.). 

 186 pages. 7±-in. X4tj-in. 



(Methuen & Co. Price 2/6.) 



This little manual, which is in continuation of one that has 

 already appeared in the same series, deals mainly with the 

 chemistry of the carbocyclic, or (as they are more generally 

 termed), the aromatic compounds. As in the case of Part I., 

 the book is simply and clearly written, and although primarily 

 intended for students in technical colleges it should be found 

 useful by all who are not far advanced in the study of organic 

 chemistry. The latter part of the book contains sections 

 dealing with practical work, including an excellent scheme 

 of qualitative analysis, but we venture to think that some 

 experimental work should have been incorporated with the 

 theoretical part. A very good feature is the description of 

 special reactions, which in many text books are merely alluded 

 to under the names of their discoverers, it being assumed that 

 the reactions themselves are common knowledge. French 

 text books are the worst offenders in this respect, but the 

 fault is not uncommon in elementary English books. 



C. A. M. 



GEOLOGY. 



Dana's Manual of Mineralogy. — By VV. E. Ford. 



Thirteenth Edition. 460 pages. 357 figures. 10 plates. 



(7}-in.X5-in.) 



(J. Wiley & Sons. Price 8/6 net.). 



This is a revised and rewritten edition of Dana's famous 

 manual, first published in 1848. It is now, however, twenty- 

 five years since the text was last revised. Whilst the figures 

 and text are new, the original scope and character of Dana's 

 book remain, and it appeals to the same constituency as 

 heretofore. The chapter on petrography has been omitted 

 and for it is substituted a brief and general description of the 

 principal rock -types. The opening section on crystallography 

 is up-to-date, and is illustrated by much better figures than 

 are usual in these text-books. This is followed by an account 



of the other physical characters and the chemical characters 

 of minerals. The treatment of determinative mineralogy is 

 rather full and renders the book of particular value to miners 

 and prospectors. In the descriptive section, occupying the 

 greater part of the book, the minerals are taken according to 

 the usual chemical classification and are treated with regard to 

 their chemical composition, crystallisation, general physical 

 properties, occurrence, and use. This section is illustrated by 

 many fine photographic plates of mineral groups, and is 

 concluded by a long and elaborate set of determinative tables. 

 A notable misprint is " Crypiocrystalline " for " Crypto- 

 crystalline " in a heading on page 176, otherwise the book is 

 very free from typographical errors. 



The section on Rocks in connection with rock-making 

 minerals would have been better for revision by a competent 

 petrologist. Such a mistake as the inclusion of anorthosite as 

 a variety of syenite might then have been avoided. Possibly 

 this is due to the megascopic mode of treatment under which 

 an anorthosite might be regarded as a " syenite " since it is built 

 mainly of light-coloured felspars. „ ... „ 



On the Origin of the Himalaya Mountains. Professional 



Paper — No. 12. Survey of India. — By Colonel S. G. 



Burrard, R.E., F.R.S. 26 pages. lli'in.X 8-in. 



(The Survey of India, Calcutta.) 



This is a concise and valuable presentation of the geodetic 

 evidence bearing on the origin of the Himalayas, whether the 

 accompanying geological theory of the author be accepted or 

 not. The plumb-line observations in the vicinity of the 

 Himalayas shew an extraordinary deficiency of mass under 

 the Gangetic alluvial belt immediately south of the mountains. 

 The deflection of the plumb-line is much greater than if the 

 Himalayas were exercising the whole of their attraction 

 uncompensated. This line of low density is supposed to be 

 due to a deep invisible trench or channel buried beneath the 

 alluvium of the Ganges. 



Colonel Burrard believes that in this region the sub-crustal 

 shell has cracked, and its northern portion has then shrunk 

 and moved away from the southern, giving rise to the folding 

 of the Himalayas. He explains the observed fact that the 

 folds are clearly overthrust to the south by saying that there 

 is only an apparent movement of the upper part of the folds 

 to the south. The real movement has been that of the under- 

 part of the folds to the north. This, of course, contradicts 

 the views of such distinguished geologists as Hayden, 

 Griesbach, and Suess, who believe that the Himalayan moun- 

 tain folds are due to horizontal thrust from the north against 

 the immobile buttress of Peninsular India. 



Whether Colonel Burrard's ingenious theory will be accepted 

 by geologists depends largely on further geological evidence. 

 It seems difficult to account for the enormous quantity of 

 alluvium that would be necessary to fill the postulated rift, and 

 further evidence of the depth- of the Gangetic alluvium is 

 needed. Also, should we not expect similar rifts in front of 

 the other great folded mountain ranges of the earth ? 



G. W. T. 



The Structure of the Earth. — By Professor T. G. Bonney, 

 D.Sc, F.R.S. 94pages. 6j-in.X41-in. (The People's Books). 



(T. C. & E. C. Jack. Price 6d.) 



It is a difficult feat to compress the story of the earth into 

 the small scope of a volume of this size, but Professor Bonney 

 has achieved the apparently impossible with remarkable 

 success. Considering the limitations of space under which 

 the book labours the resume of geological science is fairly 

 complete. The work of rain, rivers, snow, ice, and the sea, 

 and their part in shaping the surface of the earth as we now 

 know it, is treated in broad outline, with a necessary avoidance 

 of detail. Volcanoes, earthquakes, land movements, and finally 

 the history of life upon the earth, are treated in the later 

 chapters. As a simple, concise account of geology up to date 

 this small book may be recommended to beginners in the 

 science. C W T 



