SOILS — FERTILIZERS. 21 



biological absorption incieased with the alkaline character, porosity, presence 

 of easily deconiposed carbon compounds, and sutBcient nitrogen in assimilable 

 form. The absorption of ammonium and nitrate ions was dependent upon the 

 presence of the phosphate and potassium ions. The absorption of the am- 

 Uioniuni ion was from .'5.42 to 8.01 per cent greater than that of the nitrate ion. 



The general conclusion drawn is that in soil investigations, particularly as 

 regards the question of productivity, account must be taken of the biological 

 absorption as well as the physical and chemical absorption. It was found, for 

 example, that rye plants made a much stronger growth in inoculated than in 

 uninoculated, sterilized soils, thus indicating that the bacterial activity in- 

 fluenced the plant food of the soil and rendered it more readily assimilable by 

 the plants. The productive soils showed a high biological absorption not only 

 for the ammonium ion but for the phosphate and potassium ions as well. 



Biochemical relations of the phosphate ion in the soil, J. Stoklasa (Bio- 

 chemischcr Krcishitif dcx PJiosjilntt-lons ini liodcn. Jena, 1911, pp. 159, pis. 

 12). — This is a reprint in book form of matter which has in large part already 

 been noted from another source (E. S. II., 2.5. p. G24). 



The loss of ammonia from soils and experiments on the nitrogen balance 

 in pot experiments, P. Ehrenbkrg {Fuhling'n Landw. Ztg., 61 (1912), No. 2, 

 pp. JflSS). — This is a review^ of the work of O. Lemmermann (E. S. R., 26, p. 

 320), who.se conclusions agree with those of the author as to th« small losses 

 of anunoiiia from the use of ammonium sulphate, ami of A. Koch (E. S. R.. 26, 

 p. 319), who reports largo losses of ammonia from the use of ammonium sul- 

 phate under certain conditions. The author maintains* that Koch usetl much 

 larger amounts of ammonium sulphate and of lime than are ordinarily applied 

 in practice and that, therefore, his results have little or no practical signiflcance. 



The author also refers to the work of Kraus (E. S. R., 26, p. 516) as indi- 

 cating that the wind may be an important factor in influencing the rate of 

 evaporation of ammonia from the soil. 



The loss of ammonia from manured soils, P. Ehrenbebg (FiihUng's Landw. 

 Zlfj.. GO (1911), Nns. 13, pp. .'I'll-Ji-li ; l-'i, pp. 479-500).— This is a critical re- 

 view of the work of P. Lic^hti and E. Ritter (E. S. R., 25, p. 22), in which it 

 is maintained that the amount of manure used by these investigators in their 

 experiments was in excess of that which is ordinarily applied in rational sys- 

 tems of cropping and that, therefore, the results of the work as bearing on the 

 loss of ammonia have no practical value. 



The loss of ammonia from soils, P. Liechti and E. Ritter (FiihUng's 

 Landw. Ztg., 61 {1912). No. 3, pp. 83-109) .—This is a reply to the above, point- 

 ing out in a general way the fallacy of applying the results of experiments 

 with manure to those obtained with ammonium sulphate. It is held that 

 manure contains its ammonia in the form of carbonate, which is much more 

 susceptible to loss of ammonia than ammonium sulphate, and that there is 

 danger of considerable loss of ammonia when manure is applied as is ordi- 

 narily done in practice. 



Green manuring in Mysore, L. C. Coleman, B. N. Iyengar, and N. Sam- 

 PATiENGAK (Dcpt. Agv. Mysore, Gen. Ser. Bui. 1, 1912, pp. IV+22, pis. 8, figs. 

 3). — This bulletin gives the results of a 2-year study of green manuring as 

 practiced in Jlysore, particularly on paddy soils. It is shown that sunn hemp, 

 cowpeas, different varieties of gram, and avare are used to a considerable 

 extent as green manuring, but that the practice is very variable and not so 

 extensive as it should be. Suggestions regarding the improvement of methods 

 are made. 



The smells of manure works of Paris, O. Boudouard (Compt. Rend. Acad. 

 Sci. [Paris], 154 il912), No. 4, pp. 238-240; abs. in Jour. Soc. Cheni. Indus., 31 



