1919] SOILS — FERTILIZERS. 423 



composition of straw, with special reference to nitrogen, potash, phosphoric 

 acid, and lime. The kind of fertilizer had no marked influence upon the 

 nitrogen and ash content of crops on these soils. 



The acid constituents were influenced more than the basic constituents by 

 both agencies. 



The abnormality of soils in field-placed cylinder experiments, C. A. Mooers 

 [Soil Sci., 7 {1919), No. //, pp. 247-251).— In soil nitrogen studies at the Ten- 

 nessee Experiment Station five different kinds of soil, when placed in cylin- 

 ders sunk in the ground and exposed otherwise to natural conditions, were 

 found to become unproductive to the extent of complete crop failure in the 

 course of from three to eight years, except where limed. 



Annual addition of acid phosphate, potassium chlorid, and sodium nitrate 

 had little or no effect in preventing crop failure. Barnyard manure applied 

 at the outset in moderate and even large amounts delayed crop failure only a 

 year or two in most cases. The only unusual condition apparent was the 

 projection of the cylinder rims for 2 to 3 in. above the soil surface, thereby 

 preventing all run-oft of water in times of heavy rainfall. The increased 

 moisture supply and the excessive leaching were assumed to reduce the 

 natural soil supply of calcium bicarbonate until it became the limiting factor 

 in crop production and finally induced crop failure. The evidence also indi- 

 cated an increased loss of nitrogen and uncertainty with regard to the phos- 

 phorus and potassium, the availability of which may have been increased. It 

 is suggested that usual field conditions may be approached by providing each 

 cylinder with an adjustable vertical slot, providing either a constant outlet 

 or permitting run-off only at certain times of the year at the discretion of the 

 operator. 



Mining and manufacture of fertilizing materials and their relation to soils, 

 S. L. Lloyd {New York: D. Van Nostrand Co., 1918, pp. VI+153, figs. 9).— This 

 book is intended for fertilizer manufacturers, agricultural chemists, and 

 farmers desiring advanced knowledge in agricultural chemistry, and deals 

 essentially with the manufacture and mixing of commercial fertilizers from 

 the standpoint of their practical use. A discussion of the chemistry of ferti- 

 lizers and soils and of their relation is followed by a description of phosphate 

 mining and manufacturing practice, nitrogen fixation, the mining and manu- 

 facture of nitrogenous and potassic fertilizers, and the mixing of compound 

 fertilizers. 



With reference to the fertilizers resulting from the fixation of atmospheric 

 nitrogen the author summarizes experimental work with the statements that 

 " calcium cyanamid neither suits humic acid soils, peaty soils, nor light sandy 

 soils. On the other hand, it may be used in all loamy soils of average fertility. 

 . . . The action of cyanamid is weaker than nitrate of soda ; it is also 

 slower than the latter. But as the unit nitrogen is supplied cheaper by the 

 new manure, a greater amount can be used to restore the balance. . . . 

 According to the experiment made, this manure succeeds very well on clay 

 soils, but less so in sandy soils. . . . 



" Nitrate of lime acts normally up to the second application in loamy soil 

 and up to the third in sandy soil ; but beyond that there is an injurious action, 

 especially in loamy soils. The high percentage of basic nitrate of lime and the 

 still higher percentage of nitrate of lime produce injurious effects. 



" Nitrate of soda, Chile saltpetei", and sulphate of anunonia have regularly 

 produced higher yields and better utilization of the nitrogen than cyanamid." 



Two final chapters are included on the examination of fertilizers and fer- 

 tilizing materials and on the examination of soils. 

 1403G3°— 19 3 



