SOILS FERTILIZERS. 19 



Kr.-inoo. and Italy for the iiiamif.-icture of nitrogen (^■oniponnds by either the 

 Hirkeland and Eyde or the Frank and Cii'o nn^thod is noted. 



The utilization of atmospheric nitrogen for industrial purposes, 1'. F. 

 Fkankla.m) {Jour. »s'oc. Cliciii. hid us.. J(i {HXn'), A'o. .'>. /*p. 11.')- ISO. /i</s. ,i). — 

 \'arions processes wliicli liave been iiriiiioscd foi' tliis iinr])ose are descriiied. 



Experiments with lime nitrogen, nitrate of soda, and sulphate of am- 

 monia, E. Wein (Mitt. Deut. Lumlir. GcselL, 22 (1907), No. 13, pp. 128-134).— 

 ("onuarative tests of tliese fertilizers on l)arley. oats, and potatoes. 



The movement of ammoniacal nitrogen in nature, 1'. Ehrenberg (Mitt. 

 Laiiflir. In.st. Brcxloii. '/ itVol), Xo. 1-2. pp. 'i7-300, pis. 2. fifiK. .?).— This is 

 a critical monograph on this subject, including a very complete review of litera- 

 ture. It deals with the evaporation of annnonia from water, decomposing 

 organic solutions and solids, soils, and ammoniacal substances si)read on soils; 

 the leaching out of anunonia ; the transformation of annnonia into free nitrogen 

 and nitric acid (nitrification) ; tlie cheniicnl fixation of annnonia in soils and 

 outside of them; the physical fixation of annnonia: tlie fixation of annnonia ])y 

 lower plants; the taking up of annnoninni compounds l»y higher plants; and the 

 fixation of annnoniacal nitrogen by animals. 



A series of experiments made with specially constructed iipparatus to njeasure 

 tlie amount of ammonia given off by soils with and without addition of ammo- 

 niacal compounds when a current of air is swept over them at uniform normal 

 leuiperature (19-20°) is reported. 



The conclusion is reached that only in case of sandy soils rich in calcium car- 

 bonate and poor in zeolithic compounds and humus is loss of ammonia by 

 evaporation to be feared. Even in this case such loss occurs only when the 

 sunnner temperature is very high, the soil dry, and the soil content of anmionia 

 large, as in case of heavy applications of nitrogenous fertilizers. Practically, 

 therefore, the loss from this source is insignificant. 



In a series of pot experiments to study the question of assimilation of annno- 

 niacal nitrogen Ijy higher i)lants, the conclusion was reached that only nitric 

 nitrogen is suited to the needs and will insure a normal development of the 

 ordinarily cultivated higher plants. The assimilation of ammoniacal nitrogen 

 assnmes appreciable importance only in case of acid-soil and swamp-land plants. 



Nitrogenous fertilizers, L. II. Mansholt (Culturit. 19 (1901), No. 22Jf. pp. 

 260-266). — Comparative pot tests on oats of nitrate of soda, lime niter, and 

 nitrogen-lime are reported. 



Phosphates and phosphorous (['. 8. Geol. Survey Bill. 315, pp. 449-484, ftps. 3, 

 map 1 : A liter. Fert.. 26 ( 1901), Nos. 3. p. 21; 5, p. 11 ; Engin. and Min. Joitr.. 83 

 il9ol). \o. 2.7, /). 1191). — ^^rhe following papers on this subject are given in 

 (V)ntril)utions to Economic Geology, lOOt!. part 1, the first two being briefly noted 

 in the other references given : 



Phosphate deposits in Western United States, F. B. Weeks and W. F. Ferrier 

 (pp. 44!)— Kj2, figs. 3, map 1 ). — An account is given of the discovery, extent, and 

 character of important oolitic deposits of phosphate in southeastern Idaho, 

 southwestern Wyonnng, and northeastern Utah. The deposits consist of alter- 

 nating layers of black or l)rown phosphate, shale, and hard blue or gray compact 

 limestone, mainly fossiliferous. Tlie main i)ed so far developed is from 5 to 6 ft. 

 thick and contains on an average 32 per cent of phosphoric acid. 



Developed phosphate deposits of northern Arkansas, A. H. Purdue (pp. 463- 

 473). — This is ii l)rief account of the discovery, location and development, and 

 character and extent of these deposits, a report on which by the Arkansas 

 Station has already been noted (E. S. R.. 14, p. 4.30). " While it is known that 

 there is a i»liosphatic horizon of wide extent in northern Arkansas, the deposits 



