SOILS FEETILIZERS. 323 



that when the fertilizing constituents, particularly phosphoric acid, are used 

 in excess of the actual needs of the crop or out of proportion to the other 

 fertilizing constittients an injurious effect may result. 



The use of fertilizers in Spanish agriculture, A. A. de Ilera {Prog. Agr. y 

 Pecuario, J.J (IVOO), Xos. (i',5, pi). 51-'i-5l6; 6'i6, pp. 590-59.5, charts 3; 6^7, 

 pp. 606-608). — Statistics are presented of the consumption of the more im- 

 portant fertilizing materials in different provinces of Spain, 1907-8. Charts 

 show the extent of use of potash, phosphoric acid, and nitrogen. Data are also 

 given with reference to the cultivated area and the production of the principal 

 crops. 



Alpine fertilizer experiments in Carinthia, 1907-8, H. Svoboda {Ztschr. 

 Land IV. Versiirhsw. Ostcrr.. 12 <1909). Xo. 10, pp. 697-712).— The results of a 

 large number of cooperative experiments on grass lands are summarized, and 

 show very profitable returns from the use of both stable manure and commer- 

 cial fertilizers on the thin soils of the Alpine meadows. The use of either 

 manure or commercial fertilizers doubled the yield of green forage and hay, 

 and a combination of manure and fertilizers increased the yield of green fodder 

 2i fold and of hay 3 fold. 



The season and chemical fertilizers, R. Mares {Bui. Agr. Algerie et Tunisie, 

 15 (1909), No. 22, pp. 509-513).— The effect of nitrogenous, phosphatic, and pot- 

 ash fertilizers on the growth of cereals on typical soils under the climatic con- 

 ditions of Algeria is discussed. 



Method of preparation of nitrate of soda, for agricultural use, by means 

 of the nitrogen of the air and the sodium chlorid of sea water, R. Rinaghi 

 (Siaz. t^per. Agr. Ital., J,2 {1909), No. 7, pp. .'tl5-J,36, figs. 2; abs. in. Chem. 

 Zenthl., 1909, II, No. 15, p. 1281). — A patented process invented by the author 

 is described. 



The apparatus used is as follows: (1) A Hoffman voltameter with a stopcock 

 at the base of the right branch; (2) an aspirator of 10 liters capacity; (3) 

 eight Grenet cells; (4) a high potential induction coil; (.5) a fiask with 3 

 tubes, the 2 side tubes connecting with the aspirator and the nitrous vapor 

 generator, and the middle tube, provided with a stopcock, being placed under 

 the discharge of the right branch of the voltameter; and (6) a tube of strong 

 glass provided with 8 platinum points soldered inside, and with stopcocks at the 

 extremities of the tube. Sea water is put into the voltameter and on passing 

 a continuous electric current through the water by connecting 2 of the Grenet 

 cells to the voltameter, chlorin collects at the anode and hydrogen and sodium 

 hydroxid at the cathode. 



The sodium hydroxid is drawn from the right branch of the voltameter into 

 the flask described under (5) above. Electric sparks are passed through the 

 platinum points of the tube (6) by means of the induction coil and the other 6 

 Grenet cells, forming nitrous vapor which is made to pass into the flask contain- 

 ing the sodium hydroxid by opening the stopcocks of the tube and that of the 

 aspirator. A constant current of air and successive formations of nitrous vapor 

 being established, the sodium hydroxid is transformed into nitrate. 



The mass that is formed in the flask is made up of sodium nitrate, traces of 

 nitrites, alkaline hypochlorites (sodium, potassium, and magnesium), chlorids, 

 and traces of calcium, but hypochlorites oxidize the greater part of the nitrite 

 to nitrate. The liquid is decanted off and the residue dried at a low heat. 



The salt was found to contain 86.8 per cent of sodium nitrate, equal to 14.3 

 per cent of nitrogen. A theoretical calculation gives 16,022 horsepower hours 

 as the amount of power required to produce a metric ton of sodium nitrate by 

 this process. At 4 mills per horsepower hour the cost of a metric ton would 

 be $64.08. 



28918— No. 4—10 3 



