Ai'RiL 4, 1918] 



NATURE 



cal Proof," Dr. F. C. S. Schiller argues at great 

 Jength that one of the main obstacles to scientific 

 progress has been the analysis of scientific proce- 

 dure which Logic has provided, and he pleads 

 that it should abandon its pretensions to rigour 

 and conclusiveness. A philosophical treatment is 

 also adopted by Dr. J. W. Jenkinson on "Vital- 

 ism." Dr. Jenkinson was a distinguished embry- 

 ologist, who, although forty-three years of age, 

 took his commission and fell only ten days after 

 his arrival at the Gallipoli Peninsula. 



MILK PRODUCTS. 

 Manual of Milk Products. By Prof. W. A. Stock- 

 ing. Pp. xxvii + 578. (Ntew York: The Mac- 

 millan Co.; London: Macmillan and Co., Ltd., 



I1917.) Price 10s. 6d. net. 

 T^HIS book is one of the "Rural Manuals "—a 

 J- series edited by Prof. L. H. Bailey. It is a 

 very complete treatise on all matters connected 

 with the dairy industry. The general scheme of 

 the book is to bring together in one volume the 

 most recent and trustworthy information upon 

 milk and milk products. In pursuance of this 

 object, . Prof. Stocking has quoted the writings of 

 specialists in the various branches, so that the 

 student and the practical man are in a good posi- 

 tion to learn what is known on those aspects of 

 dairying which are to them of the greatest interest. 



The preliminary chapters deal with the process 

 of milk secretion, and the evidence in support of 

 the various theories is given. The much-debated 

 question as to the effect of food upon the quality 

 of milk is discussed in chap, iii., as are other 

 factors which may also have an effect — particu- 

 larly upon the fat-content of milk. Owing to the 

 fact that the standard method of estimating fat 

 in the L'nited States is by means of the Babcock 

 test, the chapter on milk testing is scarcely so 

 useful to the British reader. 



Of late years the American dairy trade has 

 nade great advance in the provision of a supply 

 t clean milk for public consumption. In New 

 Vork there are three grades of milk and cream, 

 and the regulations governing the sale are quoted, 

 as are also the score cards used in connection with 

 milk inspection. One chapter is devoted to 

 certified milk, which is used almost exclusively 

 for the feeding of infants, the cost of produc- 

 tion preventing milk of this class being avail- 

 able for any large number of the general com- 

 munity, much as it is desirable that the high 

 standard of purity should be attained for larger 

 quantities of milk. It is clear, however, that the 

 educational value of the efforts now being made 

 to get a clean milk supply must favourably influ- 

 ence the trade as a whole. 



The making of butter and cheese occupies about 

 half the space in the book, and full particulars 

 are given of all the necessary appliances and 

 machinery together with details of operations. 



There is no doubt that, with the increased 

 demand for cheese, more milk will be used for 

 NO. 2527, VOL. lOl] 



the production of the latter important article of 

 food in the future. The standard makes of 

 English cheese, such as Cheddar and Stilton, are 

 dealt with, the former variety in considerable 

 detail, as it has become the chief cheese made in 

 America. Working directions are given for 

 making a large number of other cheeses, such as 

 Gouda, Edam, Camembert, Neufchatel, cream, 

 etc. There is a chapter dealing with the part 

 played by bacteria in dairying, but this section 

 would have to be supplemented by a knowledge 

 of dairy bacteriology if the best use were to be 

 made of it. 



OUR BOOKSHELF. 



The Improvement of the Gregorian Calendar. By 

 Alexander Philip. Pp. 30. (London : G. Rout- 

 ledge and Sons, Ltd., 1918.) Price 15. 6d. net. 

 Our present calendar has many inconveniences : 

 the author's recommendations are limited to the 

 correction of the most serious. Notably, August 

 should give a day to February, reversing the re- 

 prehensible change attributed to .Augustus. If the 

 day were removed from August in one year and 

 added to February in the following year, no 

 alteration would be involved in the Easter tables. 

 Also the leap-day should come at the end of a 

 year ; its present position causes many complica- 

 tions. This might be managed, the author sug- 

 gests, by beginning the year on March i. He 

 points out the desirability of making each quarter 

 exactly thirteen weeks. He would have one day in 

 common years and two in leap years that would 

 stand outside the weekly reckoning, which would 

 thus recur exactly every year. This would be a 

 great help in the arrangement of meetings and 

 similar events, their relative positions being in- 

 variable, while at present they are subject to shifts 

 of a week. These changes would cause some 

 temporary inconvenience, especially to almanac- 

 makers, but would in the long run be a great sim- 

 plification. A. C. D. Crommelin. 



Annual Reports on the Progress of Chemistry for 

 1917. Issued by the Chemical Society. 

 Vol. xiv. Pp. ix + 264. (London : Gurney and 

 Jackson, 1918.) Price 45. 6d. net. 

 The Chemical Society commenced the practice of 

 issuing a collection of reports on the different 

 branches of chemistry fourteen years ago, with 

 the probable object of supplying to the individual 

 chemist a review of that division of chemistry in 

 which he was particularly interested. At the same 

 time, the book is to furnish the reader with a 

 concise survey of branches in which he has only 

 a general interest. These two objects seem to have 

 been attained with a fair degree of success both 

 in the previous volumes and in the present one. It 

 must be admitted, however, that the chemist who 

 endeavoured to read the book through from coyer 

 to cover would run considerable risk of suffering 

 from a severe attack of. mental indigestion. This 

 characteristic is, of course, an inevitable result of 

 the compression of a year's material into a com- 



