December 23, 1922J 



NA TURE 



839 



A good account is given of the preliminary survey 

 work that has to be done before actual operations 

 against the mosquitoes can be commenced. Mr. 

 Hardenburg insists upon the importance of a vigorous 

 propaganda to arouse public interest, and explains, 

 with some humour, how to induce newspaper editors 

 and the " motion picture houses " to " boost " the work. 



Drainage of swamps, pools, and salt marshes is dealt 

 with very thoroughly ; and detailed directions are 

 given for the construction of drains by handwork or by 

 machinery, for the laying out of a system of tile drain- 

 age, and for the construction of tide gates and sluices. 



The use of oil and other larvicides, with its advantages 

 and disadvantages, is fully considered ; and a whole 

 chapter is devoted to the use of fish to control the 

 mosquitoes. The author writes with enthusiasm on 

 this latter subject, but adopts a more judicial attitude 

 towards the proposal to establish " bat-roosts." The 

 problem of how to deal with the mosquitoes which 

 breed in rice-fields seems to be still unsolved, at least in 

 countries where the people insist upon having rice 

 cultivation near the villages. The habits of the different 

 species of Anopheles, and especially their choice of 

 breeding-places, are so varied that experience gained 

 in one country is not sufficient for dealing with the 

 conditions met with elsewhere. Now, however, thanks 

 to this book, to that of Le Prince and Orenstein, and to ■ 

 Dr. Malcolm Watson's " Prevention of Malaria in the 

 Federated Malay States." public health officers in the 

 tropics are well provided for. 



Mr. Hardenburg's book represents the views of a 

 practical man. It can be recommended with confidence 

 to all those who have to deal with sanitation in malarious 

 countries. 



The value of the book is much enhanced by the many 

 excellent illustrations with which it is adorned. 



H. J. Walton. 



Our Bookshelf. 



Das feinbditliche Wesen der Materie nack dciu Yorbilde 

 der Kristalle. Von Prof. Dr. Friedrich Rhine. 2 und 

 3 erweiterte Auflage. Pp. viii+168. (Berlin: 

 Gebriider Borntraeger, 1922.) 105. 41/. 



The new edition of Prof. Rhine's book is con- 

 siderably larger than the first edition, and presents 

 an altogether wider outlook on the fine structure of 

 matter as exhibited in crystals. The whole work is 

 enriched by an originality of treatment which renders 

 it eminently readable and suggestive. Moreover, the 

 excellent portraits of von Groth, Haiiy, Schoenflies, 

 Fedorov, Tschermak, von Laue, Debye, Scherrer, Sir 

 William Bragg, and W. L. Bragg give it an altogether 

 special interest. A reproduction of Albrecht Diirer's 

 picture " Melancholie " is also given, in which the 

 representation of a huge crystal occupies a prominent 



NO. 2773, VOL. I io] 



place, the inference being that Diirer was oppressed 

 by the idea of the hopelessness of man's ever rising to 

 the comprehension and explanation of a natural 

 phenomenon so wonderful and remarkable as that of 

 crystallisation. If Diirer lived to-day, however, how 

 different would be his picture ! It's title might well 

 be " Hope." or even " Achievement," rather than 

 " Melancholie." 



It is this extraordinary success of recent crystallo- 

 graphic and physical research, and particularly that 

 brought about by the use of X-rays in elucidating the 

 arrangement of the chemical atoms in crystals, that 

 forms the main theme of Prof. Rhine's book, and he 

 regards the whole achievement in its more fundamental 

 aspect, as having revealed the true nature of the fine- 

 structure of solid matter. The book is full of illustra- 

 tions and diagrams of an original character, including 

 many of the X-radiograms of crystals due to Prof. 

 Rhine's own industry. It is a book of very special 

 merit, and one of the most suggestive and far-seeing 

 that have appeared since the inauguration of these 

 fruitful new methods of research. A. E. H. T. 



Elementary Hydraulics for Technical Students. By Prof. 

 F.C.Lea. Pp. vii + 224. (London: E. Arnold and 

 Co., 1922.) js. 6d. net. 



Dr. Lea's larger work on hydraulics has long been 

 regarded as an authoritative treatise, and the present 

 volume will be welcomed by many who have felt the 

 need for a less comprehensive work. Beginning with 

 clear accounts of fundamental principles, the questions 

 of the flow through orifices and over notches and weirs 

 are discussed. Next follow the flow through pipes 

 and channels and the methods of gauging the flow of 

 water. Vanes, water-wheels, turbines, and pumps are 

 then considered, and the volume closes with a chapter 

 on hydraulic machines. The treatment throughout is 

 simple, which will render the book suitable for use in 

 technical schools ; the drawings are well executed, and 

 the text is very readable. A commendable feature is 

 the description of many experiments which may be 

 carried out on a comparatively small scale with in- 

 expensive apparatus. Any student who works sys- 

 tematically through the experiments described will 

 gain a very fair working knowledge of the methods 

 employed and of the manner in which the results are 

 reduced. The book also contains a number of well- 

 selected exercises, with answers ; to some of these 

 exercises hints are appended for their solution, while 

 others are left to the student. Hydraulics is not an 

 easy subject to author or student, and Dr. Lea is to 

 be congratulated upon the present volume, which 

 cannot fail to be of service to both teachers and students. 



The Czechoslovak Republic. By Jaroslav CisaF and 

 F. Pokorny. Pp. vi + 218. (London: T. Fisher 

 Unwin, Ltd. ; Prague : Orbis Publishing Co., 1922.) 

 95. net. 



The authors of this volume aimed at compiling a com- 

 plete handbook to the new state of the Czechoslovak 

 republic and have published an English edition in the 

 hope of spreading a knowledge of their country. There 

 are chapters on the history, topography, population, 

 political organisation, natural resources, industries, 

 trade, transport, etc., with appendices of statistics 



