98 



[February, 1910. 



who paid no regard to the practical 

 utility of their work and were careless 

 of the technical application of their 

 inventions. 



Modern agriculture has laid almost all 

 the pure sciences under contribution. 

 The study of pure botany for its own 

 sake has led ultimately in many cases 

 to the discovery and introduction of new 

 varieties of useful plants ; and the 

 development of miscroscopic botany 

 has led to the scientific treatment of 

 plant diseases. The contribution of the 

 zoologist is closely comparable with 

 that of the botanist, and the student of 

 evolution and heredity has arrived at 

 knowledge which can be applied to the 

 development of new and useful varieties 

 of animals and plants. 



The applications of chemistry and 

 geology to the study and improvement 

 of soils are no less obvious, although the 

 properties of soils are being discovered 

 to depend more and more upon the 

 existence of minute forms of living 

 things. Numerous other instances might 

 be cited to illustrate the importance 

 of the pure sciences as applied tc 

 agriculture. 



The developments in other arts and 

 industries which are based upon purely 

 scientific discoveries react again upon 

 agriculture. Thus the future of agri- 

 culture in the tropics is closely bound up 

 with the study of tropical diseases— a 

 study in which notable progress has 

 recently been made, whilst Piofessor 

 Sedgwick's concluding remarks give us 

 every reason for hoping that still more 

 remarkable discoveries may be expected 

 in the future. We know already that 

 with proper precautions the danger of 

 malaria can be averted to a very con- 

 siderable extent, and the bearing of this 

 fact alone upon the development of 

 tropical countries can scarcely be over- 

 estimated. 



Agricultural engineering is another 

 subject which has made great strides, 

 and the work of the engineer, no less 

 than that of the dcctor, depends ulti- 

 mately upon the labours of purely 

 scientific discoveries. 



Wherever the student of pure science 

 leads the way there is generally no lack 

 of technical experts nowadays to seize 

 upon the new discoveries and apply 

 them to industrial ends. For the latter 

 form of occupation is so much more 

 lucrative than the former that the ranks 

 of applied science are continually being 

 recruited from those of pure science at 

 the dictates of mere necessity. Although 

 the love of discovery for its own sake is 

 a powerful motive, the trend of modern 



social forces must be expected to cause 

 its appearauce in a steadily diminishing 

 number of those classes, the members of 

 which can afford to follow their own 

 inclinations ; and there is thus a danger 

 that the spirit of purely scientific dis- 

 covery may seriously decline before the 

 time arrives when public opinion shall 

 be awakened to follow the lines so ably 

 recommended by Prof. Sedgwick. 



R. H. L. 



Review. 



AGRICULTURAL FERTILISERS. 



By A. D, Hall, 



(From Nature, Vol. 81, No, 2086, 

 October 21, 1909.) 



Mr. Hall has again succeeded in pro- 

 ducing a work which will appeal with 

 equal force to the practical and to the 

 scientific agriculturist, and will do much 

 to overcome that innate prejudice of the 

 ordinary practical farmer against science 

 by showing him the enormous influence 

 science has had in determining a rational 

 system of manuring, and in giving 

 him the knowledge of a variety of 

 substances of use to him in his business 

 of food production, as well as in securing 

 for him a safeguard against adulteration 

 by unscrupulous traders. In the history 

 and evolution of the practice of keeping 

 up the crop-producing power of the soil 

 Mr, Hall examines critically the various 

 theories of manuring adduced from time 

 to time, and the experiments upon which 

 they are based, and the study of merely 

 this part of the work will be of supreme 

 importance to the practical man and to 

 the student in showing how experiments 

 may be misconstrued and conclusions of 

 the most erroneous description drawn. 



The recommendations as to the manur- 

 ing of farm crops are tempered with 

 sound advice, and the impossibility of 

 prescribing more than a generally 

 suitable method of manuring without a 

 careful study of soil and climatic condi- 

 tions extending over some years is well 

 demonstrated. Mr. Hall gives some 

 timely warnings as to deductions from 

 field experiments, of which there has 

 been such a plethora in recent years, 

 with their unscientific methods both of 

 carrying out and of deduction. The 

 importance of taking into account the 

 experimental error, which is estimated 

 at 10 %, and of neglecting results within 

 these limits should be taken to heart by 

 all who carry on these so-called " experi- 

 ments." 



