June 5, 1919] 



NATURE 



263 



point out how the same product may vary through 

 differences of climate, feeding", methods of re- 

 fining, and so on; and they then show by ex- 

 amples what deductions may legitimately be 

 drawn from the experimental data. 



The substances dealt with include hydrocarbon 

 oils and waxes, rosin, turpentine, soap, glycerin, 

 and candle material, as well as the animal and 

 vegetable oils, fats, and waxes. The book 

 appears to be well "up to date," and can be 

 recommended as a very useful addition to the 

 technical chemist's library. C. S. 



OUR BOOKSHELF. 

 Joys of the Open Air. By William Graveson. 



Pp. 115. (London: Headley Bros., Ltd., n.d.) 



Price 35. 6d. net. 

 To the town-dweller who has a longing for the 

 countryside, more especially in the dull, damp 

 early months of the year, when spring seems so 

 long in coming, the chapters of this little book 

 will serve as a tonic. Mr. Graveson is a man 

 Vvho loves his garden and his bird-visitors, as well 

 as the meadows, woods, and chalk-downs beyond ; 

 he has eyes that can see, and above all he has the 

 faculty of expressing what he sees and feels in 

 simple, charming language. 



In this delightful little volume he has jotted 

 down some of his experiences during the months 

 from February to September of last year. He 

 shows how, when exactions of business and vari- 

 ous duties curtail hours of recreation, and diffi- 

 culties of travel prevent holidays from being taken 

 far afield, there are opportunities for seeking new 

 pleasures in familiar surroundings. The rambles 

 described in his book have been in the compass of 

 a half-holiday walk and not more than five miles of 

 a country town within easy distance of London. 

 The arrangement is chronological. Chap, i., 

 "The Haunt of the Kingfisher," describes a 

 bright morning early in the year when the hoar- 

 frost lies thick on the common. "The Promise of 

 Spring " (chap, ii.) recalls the coming of the 

 winter aconite, the crocus, and other harbingers 

 of spring. "The Incoming of Spring " is an epic 

 of a sunny Palm Sunday — daffodils and scillas 

 are out in the garden, a silky-coated Pasque- 

 flower is preparing for its Easter display, and a 

 bright red anemone for the warm April days ; and 

 never have the almonds looked more beautiful. 

 And so on through the book to "Foxgloves and 

 Fairies " and "The Lure of the Heather," which 

 are the headings of the two last chapters. 



The illustrations, photographic reproductions — 

 a stream choked with water-violet, a bed of winter 

 aconites, a cowslip meadow, and a few others — 

 add to the charm of this series of Nature pictures. 



Submarine and Anti-Suhmarine. By Sir Henry 



Newbolt. Pp. viii4-3i2. (London : Longmans, 



Green, and Co., 1918.) Price ys. 6d. net. 



Sir Henry Newbolt has succeeded in presenting 



1 very fair view of the work of our submarines 



and of the measures taken to meet the U-boat 



menace. Despite the fact that a great deal of 



NO. 2588, VOL. 103] 



further information has been published since the 

 date of the armistice, the book will be found to 

 be useful on account of the connected present- 

 ment. Opening with the evolution of the sub- 

 marine and a description of the submarine of 

 to-day, the author passes to the methods of the 

 submarine in attacking warships, and the means 

 taken by warships in meeting attack and in 

 aggressive action. The work of our submarines 

 in the Baltic and in the Dardanelles occupies a 

 large section of the volume, and the work of our 

 trawlers, destroyers, P-boats, and Q-boats is well 

 described. The book closes with an account of 

 the Zeebrugge and Ostend attacks. 



One interesting aspect of the submarine cam- 

 paign is a knowledge of the feelings of the hunted 

 during the chase. This is dealt with in chap, xvi., 

 by quoting a long extract from the "War Diary 

 of LI 202," by Lt.-Commdr. Freiherr Spiegel von 

 und zu Peckelsheim. Sir Henry Newbolt comments 

 on the extract by saying that it is not unnatural 

 that von Peckelsheim should enlarge upon his 

 terror at the moment and his self-congratulation 

 afterwards. But his diary contrasts badly with 

 repKjrts from our own submarine commanders in 

 worse circumstances. "We may take pleasure 

 in noting that the steadiness of nerve and the 

 scientific view are in our favour." 



Aids in Practical Geology. By Prof. Grenville 

 A. J. Cole. Seventh edition, revised. Pp. xvi + 

 431. (London: Charles Grif!in and Co., Ltd., 

 1918.) Price los. 6d. net. 

 There are few living authors who take so wide 

 a view of the phenomena and problems of geo- 

 logy as Prof. Cole, and none who is more 

 capable of making the subject of interest to the 

 student. He stands out, too, among his contem- 

 poraries in his appreciation of the work of the 

 pioneers of the science, and in particular of the 

 French petrologists of the first half of the nine- 

 teenth century, especially of Cordier and Delesse. 

 He gives an interesting record of the latter's pro- 

 cedure in determining the volumetric mineral com- 

 position of a rock by the measurement of areas 

 on a polished slab, and explains how it may be 

 applied to sections under the microscope. Prof. 

 Cole does not, however, refer to the linear method 

 in which the same result is obtained by the 

 measurement of the mineral intercepts on lines 

 drawn over the surface. This method, which has 

 largely superseded the area method in microscopic 

 work, was described by Delesse in the same paper, 

 though the credit for it is usually given to 

 Rosiwal, who published an account of it just fifty 

 years later in 1898. 



In the limited space at the author's disposal it 

 was impossible to include everything he might 

 have wished, but perhaps in a new edition he 

 will endeavour to find room for the shadow 

 (SchrSder van der Kolk) method of determining 

 under the microscope the refractive index of 

 grains or fragments relatively to the medium in 

 which they are immersed. It is at once very 

 simple and easily applied. J. W. Evans. 



