626 EXPERIMENT STATION RECORD. 



matter content into (1) beech, heath, and black molds, and (2) forest molds. 

 The beech, heath, and black molds were rich in mineral matter, but low in 

 organic matter. The forest molds were low in nitrogen and phosplioric aci<l. 

 There was substantially no difference in the moisture of the 2 classes of 

 molds, but the forest molds had a higher retentive power for water. 



Methods for arresting and utilizing moving alluvial mud (Rev. Sci. 

 [/'oml, J,8 (IDIO), II, Xo. 20. p. 628; ahs. in Intcrnat. Inst. Agr. [Rome}, Bui. 

 liar. Agr. Intel, and Plant Disease.'^, J910, Xo. 2, pp. 213, ,?///).— The mud along 

 the Rhine and Meuse near Rotterdam is arrested and held by planting first 

 Scirpus lacustris and later riiragniitcs communis, and is thus eventually ren- 

 dered fit for gi-asses and sugar beets. 



The maintenance of soil fertility, C. E. Thorne (Quart. Rpt. Kans. Bd. 

 Agr., 30 (1911), No. 117, pp. 92-106).— The author describes the methods of 

 maintaining soil fertility employed at the Ohio Station, reaching the general 

 conclusion " that in the present stage of the world's development this end is to 

 be attained most economically through the production of live stock and the 

 systematic saving and utilization of the resulting waste products, both at the 

 stable and at the slaughterhouse; supplementing these products from the de- 

 posits of the mineral stores of combined nitrogen, phosphorus, and potassium ; 

 keeping the soil sweet with lime; and so adjusting our system of cropping as 

 to provide for the greatest possible use of the nitrogen-gathering crops." 



The feeding of crops and stock, A. D. Hall (London, 1911, pp. XVI-{-298, 

 pis. 23, fig. 1). — This latest book by the director of the Rothamsted Experi- 

 mental Station is described as an introduction to the science of the nutrition of 

 plants and animals, which is intended " to give the student of agriculture a 

 general framework of ideas before he enters upon the more detailed study of 

 agricultural chemistry," and thus enable him to understand better and profit 

 more from the later instruction in this subject. It is thought that the book 

 will also be useful to the many students " who do not as a rule pursue the sub- 

 ject any further than it is carried in these pages," but " even more than for 

 the student, this book is intended for the workaday farmer who wants to get 

 an intelligent conception of how his crops and stock make their growth." 



The author is of the opinion that " it should neither be difficult nor tedious 

 for the man with an ordinary education to leai'n how a plant draws its nutri- 

 ment from the soil and how the animal depends in its turn upon the plant. . . . 

 Complex and unknown as many of these processes are, the main outlines are 

 sufficiently established to have a bearing upon practice ; but the practical appli- 

 cation can be more surely and readily made if the farmer, with his inside knowl- 

 edge of the way things can be done, will learn the theory than by any attempt 

 of the scientific man striving from the outside to get up the working conditions." 



The book is written as far as possible in nontechnical language, and it is 

 assumed that the reader possesses little or no knowledge of chemistry. The 

 main facts and principles are illustrated by numerous simple experiments. 

 Different chapters deal with what the plant is made of, the work of the leaf, 

 the work of the roots, changes of composition within the plant, the origin and 

 nature of soils, cultivation and the movements of soil water, the living organ- 

 isms of the soil, the chemical composition of the soil, foods, the utilization of 

 food by the animal, food required by the growing and fattening animal, farm- 

 yard manure, artificial manures and fertilizers, and milk, butter, and cheese. 



Soil improvement, P. Van Hoek and A. Rauwerda (Dept. Landh., Nijv. en 

 Eandl., Verslag. en Meded. Dir. Landb. [Netherlands], 1911, No. 1, pp. 45-53). — 

 This article summarizes the results of tests conducted at different places in 

 the Netherlands in the improvement of heath soils by green manures and 

 mineral fertilizers, the fertilizing Aalue of sea mud, stable manure versus 



