io6 



NATURE 



[September 23, 1920 



the botany of Surrey the late George Massee leaves 

 a curious note of chronology by saying (p. 65) : 

 "The edible boletus (Boletus eduUs) has a cap 

 corresponding in size and colour to a penny bun." 

 When will the penny bun once more rival the cap 

 of a boletus? 



Practical Organic Chemistry. 



The Preparation of Organic Compounds. By 

 E. de Barry Barnett. Second edition. Pp. 

 XV + 273. (London: J. and A. Churchill, 

 1920.) Price 105. 6d. net. 



THE work which the universities were invited 

 to undertake in preparing synthetic drugs and 

 "poison gases" in more than usual laboratory 

 quantities forced them to replace their costly glass 

 and porcelain apparatus, wherever possible, by 

 larger and stronger vessels of tinned iron and by 

 earthenware basins of cheap material. This ex- 

 perience has been wisely turned to account in the 

 new edition of Mr. Barnett's book, in which a 

 description of such apparatus is given. Although 

 it is desirable for the beginner to use transparent 

 vessels, in which reactions can be easily watched 

 and controlled, and to manipulate quantities which 

 do not demand too great an expenditure of time, 

 the knowledge of how to apply larger scale 

 methods he may later be called upon to adopt will 

 prove invaluable. Moreover, the habit of discard- 

 ing, as occasion demands, the usual laboratory 

 vessels in favour of less elegant but more service- 

 able utensils is a good mental and moral exercise. 

 With the exception of the above-mentioned de- 

 scription and the addition of a few new prepara- 

 tions, no fundamental change has been made in 

 the size and scope of the new edition. It takes 

 the form made familiar by Gattermann's and 

 Freundler's well-known treatises, and by many 

 other books dealing with this subject. 



Which of the two systems is the more satis- 

 factory, namely, discussing general methods and 

 apparatus first, and then referring to them in the 

 later preparations, or allowing the student to 

 familiarise himself with them by actual examples 

 involving their use, must be left to the individual 

 teacher to decide. He must also determine what 

 amount of detail he thinks it desirable to supply 

 in his account of the preparations. There is no 

 doubt that some simple modification in the con- 

 duct of a reaction which additional details would 

 supply will often convert failure into success, with 

 a corresponding economy in the student's time. 

 On the other hand, advantage may be gained by 

 the student having to surmount his own diffi- 

 culties. 



NO. 2656, VOL. 106] 



There is, on the whole, not much to choose 

 between the two methods. The present writer is 

 inclined to think that, as the purpose of the prac- 

 tical work is mainly to assist the student in 

 developing his general knowledge of organic 

 chemistry, the greater the variety of reactions 

 he can perform during his course, which is 

 often not too long, the more he will profit by 

 it. Later research will afford ample opportunity 

 for the exercise of his ingenuity in meeting and 

 overcoming difficulties. J. B. C. 



Our Bookshelf. 



The Essentials of Histology : Descriptive and 

 Practical. For the Use of Students. By Sir E. 

 Sharpey Schafer. Eleventh edition. Pp. xii-f 

 577. (London : Longmans, Green, and Co., 

 1920.) Price 14s. net. 

 "The Essentials of Histology" preserves, in its 

 eleventh edition, the well-known characteristics of 

 the previous editions of this standard work. The 

 volume is growing in size, but the additions are 

 mainly of new illustrations. These are uniformly 

 good, and conform to the general tendency of suc- 

 cessive editions to present photographic represen- 

 tations of actual preparations, as well as semi- 

 diagrammatic drawings emphasising points which 

 the artist deems of special import. The latter are 

 of great service to the beginner, but carefully 

 selected photographs mean more to the advanced 

 student. Both varieties are utilised in the 

 "Essentials," and monotony in the figures is 

 avoided by a pleasing use of colour. Although 

 mainly a descriptive work, the practical side is 

 better represented than a cursory glance would 

 reveal, and the directions briefly given at the head 

 of each lesson are amply sufficient, if exactly fol- 

 lowed, to enable the student to obtain the pre- 

 parations desired. Further practical directions are 

 given in the appendix, which is a synopsis of 

 general and special histological methods. 



A Naturalist on the Amazons. By H. W. Bates. 

 Abridged and edited for schools by Dr. F. A. 

 Bruton. (English Literature for Secondary 

 Schools.) Pp. xix+i82. (London: Macmillan 

 and Co., Ltd., 1920.) Price 2s. 6d. 

 In this abridged edition selections from Bates's 

 original work have been chosen which deal 

 mainly with the natural history of the forests of 

 the Amazon. A short account of the more re- 

 markable forest trees is included, but the bulk 

 of the book consists of selections describing the 

 fauna of the country. Illustrations from photo- 

 graphs are given of most of the animals men- 

 tioned. Dr. Bruton contributes an interesting 

 introduction and some helpful notes. We are glad 

 that Bates's vivid descriptions of Nature and man 

 are made available for appreciation by young 

 people in schools by the issue of this abridged 

 edition of his masterpiece. 



