SOILS FERTILIZERS. 319 



Soils and manures, J. A. Murray (London, WW, pp. XIII+35'i, fiffs. .?.?). — 

 This book attempts to present tlie fundamental facts and principles of soil 

 fertility and treats the subject from the scientific point of view. Some previous 

 bno\\-]edj:e of chemistry is considered necessary to its proper understanding. 



" The facts and figures selected to illustrate established principles have been 

 chosen, as far as possible, from the Rothamsted records, partly on account of 

 their recognized reliability and partly, also, because these classic researches 

 are likely to prove of greater interest to English students than others which 

 have been carried out abroad." 



Different chapters deal with the origin of soils, physical properties of soils, 

 chemistry of soils, biology of soils, fertility, principles of manuring, phosphatic 

 manures, phospho-nitrogenous manures, nitrogenous manures, potash manures, 

 compound and miscellaneous manures, general manures, and farmyard manure. 

 Appendixes give instructious for valuing manures issued by the Highland and 

 Agricultural Society of Scotland and the estimated manurial value of the com- 

 moner kinds of feeding stuffs. 



Plain talks on the use of fertilizers, E. B. Voorhf:es ( Farmers Digest, Jf 

 {1910), Nos. 1, p. 6; 2, p. U). — This is a continuation of the article on this 

 subject already noted (E. S. R., 22, p. 430). 



Farm practice in the use of commercial fertilizers in the South Atlantic 

 States, J. C. Beavers (U. S. Dept. Agr., Farmers' Bui. 3US, pp. 2',, figs. 2).— 

 According to this publication, there is a lack of accurate information regarding 

 the economic use of fertilizers, and " with a good rotation, deep and thorough 

 tillage, and the use of green manures, legumes, and winter cover crops, the quan- 

 tity of commercial fertilizers required for a given crop yield can be consider- 

 ably reduced. 



" The character of the soil has a marked influence on the quantity and kind 

 of fertilizer it is necessary to use in a good system of farming. 



'• In farm practice there is a gradual increase in the quantity of all the fer- 

 titlizer constituents required to produce like yields as the proportion of sand in 

 the surface and subsoil increases. The increase is greatest in the quantity of 

 potash necessary, followed by phosphoric acid, and then by nitrogen. 



"A study of farm practice shows that the best farmers . . -. obtain yields 

 of 1 to 2 bales of cotton, 40 to 75 bu. of corn, and 40 to 75 bu. of oats on soils 

 where [poorer] farmers . . . get but one-half to 1 bale of cotton, 15 to 40 

 bu. of corn, and 15 to 40 bu. of oats, due to the fact that the best farmers have 

 a better understanding of the use of fertilizers and employ better farm methods. 



" One of the most common grades of fertilizer on the market in the South 

 Atlantic States at present contains 8 per cent of phosphoric acid, 3 per cent of 

 ammonia, and 3 per cent of potash. This grade of fertilizer is of primary value 

 only for cotton on red clay soil under fairly good methods of rotation. This fer- 

 tilizer formula needs to be greatly modified for crops on sandy, sandy loam, and 

 gray loam soils, and for all crops other than cotton on red clay soil. 



" Detailed suggestions are contained in this bulletin on the best method of 

 fertilizing and the most ])rofifable kinds of fertilizer constituents to apply on 

 soils of different character to cotton, corn, oats, wheat, and cowpeas." 



Pot culture experiments, 1908, J. A. Voelcker (Jour. Roy. Agr. Sac. Eng- 

 land, TO (1000), pp. 38.'i-395).—The subjects of these experiments were the 

 influence of lithium and potassium salts on wheat, the influence of colloid sub- 

 stances on the productiveness of soils, the Influence of magnesia in soils, 

 fertilizers for fen soils, continuous culture of barley on an acid soil, and inocu- 

 lation of leguminous crops. 



Continuing the experiments of i)revious years with lithium and potassium salts 

 it was found that the former were injurious to wheat plants, the carbonate 



