388 



NATURE 



[August 27, 1903 



Carlsberg laboratory, and embodying the ideas and 

 teaching of Hansen himself. It is welcome also to 

 English readers from the fact that it has been trans- 

 lated in great part by one of the disciples of the Burton- 

 on-Trent school, from which have come so many 

 valuable contributions to our knowledge of the 

 chemistry of the carbohydrates concerned in brewing. 



The author has described at great length what we 

 may consider to be an ideal laboratory for the practical 

 study of the lower fungi, including, indeed, the patho- 

 logical bacteria, though these are not necessarily in- 

 cluded in the range of study he sets forth. His de- 

 scription is greatly to be commended, for he is not 

 satisfied with saying what apparatus should be pro- 

 vided and what precautions observed in arranging tne 

 laboratory, but he gives a careful explanation of the 

 reasons underlying his plans, so that mere empirical 

 work has no place in this course. The descriptions of 

 apparatus are good, showing what are the best forms 

 of the modern appliances now at the disposal of 

 workers at the subject. Perhaps a little less detail 

 would have sufficed in the section upon the microscope, 

 as the instrument has now so widespread an appli- 

 cation in so many branches of science. Workers will 

 welcome especially the instructions given in the 

 methods of culture of micro-organisms, from the 

 original methods of water culture of Hansen to tne 

 modern plate cultures, in which gelatin and similar 

 media take so large a part. 



A very important section of the work is devoted to 

 the biological analysis of yeasts, and the methods of 

 ensuring pure cultures. Also to the biological analysis 

 of water, air, and soil. 



In the later portion of the volume the author treats 

 in some detail of the fermentation organisms them- 

 selves. In this section the Saccharomycetes occupy 

 the largest place, as is natural when we consider the 

 fermentations in which they play a part. Mucor and 

 its allies, however, are not neglected, and fair attention 

 is given to the ascomycetous moulds. Their diagnostic 

 features are described, and the part they play in various 

 fermentations is discussed, the idea being kept promin- 

 ently in view that the author is writing as a teacher 

 for students, and that the work is a laboratory hand- 

 book. Finally, the bacteria come in for recognition. 



The book will be welcomed further for the very 

 admirable historical sketch of the gradual development 

 of our knowledge of fermentation from the earliest 

 times. It is very satisfactory to find that this section 

 contains an admirable summary of the work of Hansen 

 himself. 



The volume concludes with a very complete biblio- 

 graphy. 



OVR BOOK SHELF. 

 Five Figure Logarithmic and other Tables. By Alex. 



M'Aulay, M.A. Pp. xl + i6i. (London : Mac- 



millan and Co., Ltd., 1903.) Price 2s. 6d. 

 Siebenstellige Logarithmen und Antilo garithmen. By 



O. Dietrichkeit. Pp.64. (Berlin : Julius Springer, 



1903.) Price 3 marks. 

 The book by Mr. M'Aulay is of a very handy size, 

 specially adapted for the pocket. The author, in the 

 preliminary pages, explains the general properties of 



NO. 1765, VOL. 68] 



logarithms and the use of the tables which follow. 

 The tables themselves comprise, first, an ordinary four- 

 figure table of logarithms of numbers, occupying two 

 pages, and without the usual antilogarithms. Next, 

 a five-figure table of logarithms of numbers from o to 

 100,000, with a complete set of proportional parts or 

 differences ; these take up thirty-six pages. Then 

 comes the second principal table of the book, giving 

 the logarithmic sines, cosines, tangents, and cotan- 

 gents of angles for each minute, with differences for 

 intervals of ten seconds. Some subsidiary tables and 

 useful numbers follow, very much condensed, so as 

 not materially to add to the size of the book. 



The tables would be improved if they could be pro- 

 vided with a marginal or thumb index to facilitate 

 reference. The two main tables are printed in clear 

 bold type, and the little volume will prove extremely 

 useful to all who require greater accuracy than is 

 given by four-figure mathematical tables. 



The tables of Herr O. Dietrichkeit are most 

 ingeniously arranged. The numbers in the columns 

 are given to seven figures, the last two of which are 

 written as suffixes in smaller type. Tlji^ logarithm or 

 anti-logarithm of any four-figure numb^f^^pan be read 

 directly from the tables to any desired accuracy up 

 to seven figures without requiring differences to be 

 used. The two tables of logs and anti-logs are printed 

 on paper of different tints, a very good feature, and 

 they occupy only eighteen and twenty pages respec- 

 tively. They are provided with a complete thumb 

 index, reading both backwards and forwards, and it 

 will be found that readings may be taken from the 

 tables almost, if not quite, as quickly as from the well- 

 known four-figure tables. 



If five-figure accuracy were required for five-figure 

 numbers, the difference for the fifth figure would have 

 to be calculated. And it is possible from these tables, 

 although occupying only a few pages, to obtain seven- 

 figure accuracy for seven-figure numbers, by means 

 of an interpolation constant and a most ingenious 

 method of calculation, which, however, would be too 

 long except for occasional use. The tables will prove 

 most valuable in cases where, though four-figure 

 accuracy is usually sufficient, it is desired to have at 

 command a means of greater accuracy for special pur- 

 poses. The volume is beautifully got up and printed, 

 and it is quite a pleasure to use the tables. 

 Economie rurale. By E. Jouzier (Encyclopedie 

 agricole). Pp. xv + 476. (Paris: Bailliere et Fils, 

 1903.) Price 5 francs. 

 This book belongs to a type of which we have few 

 representatives in this country; it consists of a dis- 

 cussion of such general principles of political economy 

 as may be illustrated in the conduct of a farm. 



Beginning with an account of the relations of agri- 

 culture to the State, questions of taxation, transport 

 and markets, it proceeds to discuss the capital required 

 in the business of agriculture, the live and dead stock, 

 insurance, depreciation, and the valuation of such con- 

 tingencies as cultivations and manurial residues. 

 Such general principles as the minimum of production 

 necessary to profit and the law of diminishing returns 

 are explained and illustrated. Questipiis^ of labour, 

 rriethods of finding the cost and profit or'^loss of the 

 different operations are considered ; finally, tenure, 

 compensation for improvements, systems of land hold- 

 ing, cooperation, and similar matters touching on the 

 economics of agricultural production are dealt with. 

 The whole is treated in a somewhat abstract and 

 generalised fashion, and would find little favour with 

 the practical farmer or landowner here; we can, how- 

 ever, commend the book to teachers of agriculture 

 as suggestive and likely to lead to a wider outlook 

 than generally prevails in the treatment of similar 

 questions in this country. 



