SOILS FERTILIZERS. 519 



them to exist, are largely responsible for the unproductiveness of the soil in 

 question." 



The toxicity is overcome and the soil rendered productive by adding com- 

 pounds such as those of calcium, which possess the common property of pre- 

 cipitating the aluminum and at the same time forming nontoxic salts with its 

 acid radical. 



"Application of pulverized limestone or shiked lime at the rate of 2 to 

 4 tons per acre, supp]emente<l l)y fertiliKation with phosphates and potash, 

 has proved effective in field trials on a large scale and is recommended as a 

 practical remedial treatment for rendering this type of soil productive." 



The law of minimum, K. von Kumker {Fiihling's Landw. Ztg., 62 {1!)13), 

 No. 21, i)p. 772-77^). — The author maintains that the law of minimum applies 

 not only to the external crop and culture relations but also to the racial per- 

 formance of cultivated crops. 



The influence of fertilizing" on the resistance of grain to hail, Gaul (Deut. 

 Landw. Pressc, 40 {1913), No. 104, V- 1252).— Rje, unfertilized or fertilized with 

 manure, showed a poorer stand and was less resistant to hail than that fer- 

 tilized with superphosphates and kainit. Rye fertilized with nitrogen was 

 strongly develoi)ed and showed great resistance, and in this respect anmionium 

 sulphate appeared to give stronger and more resistant straw than sodium ni- 

 trate. Kainit also strengthened the straw and increased resistance. 



A brief account of trials with lime fertilization, P. Bolin {Meddel. Central- 

 anst. Forsoksv. Jordhruksomrddet, No. 80 (1913), pp. 7; K. Landtbr. Akad. 

 Handl. och Tidskr., 52 (1913), No. 4, pp. 282-286).— In field trials during the 

 season of 1911-12, lime was applied with sodium nitrate, Thomas slag and 

 potash salt, farm manure, and farm manure with Thomas slag and potash salt, 

 to green oats and hay. 



The lime applied with artificial fertilizers did not produce any beneficial 

 effect over that of artificial fertilizers alone, but increased the yields obtained 

 in a marked manner when it was applied with farm manure, or with farm 

 manure and artificial fertilizers. This was especially true in the case of the 

 plats that had received lime (and manure) the preceding year. The favorable 

 results obtained with lime and manure are attributed to the beneficial effect 

 of the lime on the utilization of the nitrogen in the farm manure. 



Lime-magnesia fertilizers, E. Mabre (Prog. Agr. et Vit. (Ed. VEst-Centre), 

 S4 (1913), No. 47, pp. 657-664). — In field experiments on different soils the 

 yields were generally profitably increased by the use of a fertilizer containing 

 43 per cent of lime and 30 per cent of magnesia, the results being especially 

 favorable when the fertilizer was used in connection with Thomas slag. 



Lime-magnesia ratio in the cultivation of grain, F. Pisciotta (Staz. Spcr. 

 Agr. ItaL, 46 (1913), No. 10, pp. 643-660) .—Analyses of 60 Italian soils showed 

 a wide variation in the lime-magnesia ratio, due principally to the variation 

 in the lime. It was equal to 1 in only 1 soil and less than 1 in 4 soils. The addition 

 of 40 lbs. of magnesium sulphate per acre to soils increased the grain yield, 

 when added at the time of seeding, sufficiently to oft'set the expense of fertili- 

 zation and yield a good net profit. When the magnesium salts were added in 

 the spring, the profit was very small or negative. The best yield was obtained 

 in soils with a high lime-magnesia ratio, but contrary to the theory of Loew 

 a profitable increase was also obtained in soils having a lime-magnesia ratio 

 less than unity. 



Sponges as a fertilizer, J. G. Smith (Jour. Indus, and Engin. Chem., 5 

 (1913), No. 10, p. 850). — It is stated that sponges, which grow in enormous 

 quantities in the shallow waters of southern Florida, are used with good re- 

 sults as a fertilizer. 



