REVIEWS 521 



observation — and can testify to the value of the evidence. But bacterised peat 

 by no means always produces such marked effects, and indeed we have seen 

 trials in which it has produced no favourable results at all. Wherefore, although 

 there is positive evidence in favour of the high manurial value of bacterised 

 peat, we cannot admit that the evidence is final and complete. Nor do we yet 

 know what kinds of peat are susceptible of use for the production of bacterised 

 peat. We believe that Prof. Bottomley has hitherto used peat moss litter as 

 his raw material ; but on this point we are without certain knowledge. 



Any plant physiologist who has ever coaxed a minute seed, sown in pure 

 sand and watered only with a mineral culture solution, to grow into a large 

 flowering and fruiting plant, will be excused if he hesitates to accept the theory 

 of auximones — even on the evidence presented by Mr. Knox, striking though 

 that evidence may be. The truth is that existing biological methods of testing 

 such claims as these are clumsy and treacherous, as all who have experience 

 of experimental plots know to their cost. Many repetitions of the original 

 experiments will require to be made before the claims of Prof. Bottomley are 

 regarded by experts as established. In the meantime he would indeed be a 

 hypercritical curmudgeon who denied that Prof. Bottomley has done a piece 

 of work which holds out the promise both of benefiting horticulture and 

 agriculture and of modifying profoundly our views on plant-nutrition. 



Frederick Keeble. 



The Essentials of Agriculture. By Henry Jackson Waters. [Pp. x+455 

 + xxxvi.] With numerous illustrations. (Ginn & Co., Boston, U.S.A., 

 191 5. Price $s. 6d. net.) 



The title of this volume raised hopes which the preface disappointed by stating 

 that it is merely "for students who desire a practical working knowledge of the 

 essentials of agriculture," and the practical farmer would probably reduce these 

 to one only, namely, to make things pay. At the same time it is a book which 

 any English farmer might peruse with interest, if only because its Transatlantic 

 origin leads to a wide treatment in such matters as the relation of the farmer 

 to the community at large ; in discussion of labour in regard to machinery and 

 cultivation methods, of man-yield and acre- yield, and so forth. 



The illustrations are a good feature, though several might be much larger 

 to do themselves justice. Some are almost startling to residents of the old 

 country, such as the picture of a modern wheat-heading and -threshing machine 

 drawn by thirty-three mules. Others are pictures of methods employed by 

 native races in various parts of the world, shown to emphasise the contrast 

 between backward and progressive races ; those who know something of both, 

 and of the labour-cost in the U.S.A., will perhaps be less impressed by the 

 contrast. The authors — for the book is a joint production by many specialists — 

 display a faithful belief in progress which might convince even a cynic, though 

 occasionally they adduce evidence to the contrary, such as the statement that 

 "dry-farming" (which was widely advertised a few years ago) is a very old 

 practice of the Chinese. 



A readjustment of the headlines in several places would facilitate the student's 

 task; the spelling of " reenforce " on p. 97 seems to come from an unknown 

 tongue ; and the Egyptian cotton crop on p. 178 is stated at only one-third of 

 its actual amount. 



Accepting the view that an ordinary agricultural student can derive knowledge 



34 



