326 EXPEKIMENT STATIOIST RECORD. [Vol. 41 



electrical precipitator. Experiments conducted on a semicommercial scale indi- 

 cate that such a collection is possible." 



Electro-potash, a Swedish potash fertilizer, and its effect upon mineral 

 soils, P. Eheenbekg et al. (Jour. Landio., 66 (1918), No. Jf, pp. 209-2JfO). — Pot 

 experiments with wheat and buckwheat are described in which a comparison 

 was made of a potasli fertilizer designated as electro-potash with sulphate of 

 potash and a 30 per cent potash salt in both lim(>d and unlimed sandy and 

 loam soils. The electro-potash, said to contain about 11 per cent HCl-soluble 

 potash, is secured as slag alter fusing either a grauulitic rock or potash 

 gneiss or feldspar with charcoal and iron ore in the electric furnace. The 

 results are held to indicate that the new material is inferior to the two potash 

 salts, both in its effect upon the j'ield of dry matter and its availability to the 

 plant. 



The limestones of Canterbury considered as a possible source of phosphate, 

 L. J. Wild and R., Speight (New Zeal. Jour. Sci. and TecJtnoL, 2 (1919), No. 3, 

 pp. 180-192). — The character, extent, and possible fertilizing value of these 

 limestones are discussed. They are shown to contain variable amounts of 

 impurities, mostly sand, but many of them contain sufficient phosphate to be of 

 considerable importance for fertilizing purposes. Analyses of a number of 

 samples of the limestones shov»^ed from 0.16 to 3.14 per cent of phosphoric 

 acid, while certain of the nodules associated with the limestones contained 

 from 10.6 to 51.S per cent of tricalcium phosphate. 



The action of some common soil amendments, J. E. Geeaves and E. G. Cae- 

 TER (Soil Sci., 7 (1919), No. 2, pp. 121-160, figs. 2). — An extensive review of the 

 work of the authors and others bearing on the subject is given, and experiments 

 conducted at the Utah Experiment Station are reported on the effect of 17 

 different salts, including the sulphates of magnesium, calcium, manganese, and 

 iron, the chlorids of sodium, iron potassium, magnesium, manganese and 

 calcium, the nitrates of calcium, potassium, magnesium, and manganese, and the 

 carbonates of manganese, iron, and magnesium, or the available nitrogen 

 and phosphorus of soil. 



It was found that the increased available nitrogen and piiospliorus is suffi- 

 cient to account for the noted increase in crop yields resulting from the use 

 of these soil amendments. The increase in nitric nitrogen varied from 1 to 

 96.7 per cent. The water-soluble phosphorus was increased by all but 5 of the 

 17 salts, the increase varying from 0.2 to 15.5 per cent. Three of the salts 

 which failed to increase the water-soluble phosphorus increased the organic 

 phosphorus, hence the availaWe phosphorus was increased by all but 2 of the 

 17 salts listed. The increase in organic phosphorus varied from 3.3 per cent 

 with calcium sulphute to 62.6 per cent with manganese carbonate. The strong 

 stimulant sodium chlorid acted to a great extent by rendering phosphorus 

 soluble, whereas the equally strong stimulant calcium sulphate acted by 

 rendering available more nitrogen. 



Use of sludge as a fertilizer, F. T. Hambleton (Engin. and Contract., 51 

 (1919), No. 18, p. 1(46). — It was found that the expense of disposal of the sludge 

 from a sewage plant yielding 500,000 gal. of sludge per year was met by the 

 proceeds from the crops obtained from 6 acres of land to which the sludge was 

 applied in liquid form. Mixing the sludge with phosphatic and potassic fer- 

 tilizers gave even more profitable results. 



Fertilizers, P. A. Lopez DomInguez (Porto Rico Dept. Agr. Sta. Bui. 18 

 (1919), Spanish Ed., pp. 79). — This publication comprises a rather detailed but 

 general discussion of the relations between plants, soils, and fertilizers, together 

 with informutiou relative to the regulation of the sale of fertilizers, particu- 



