FERTILIZERS. 765 



Experiments in which 445 lbs. of sodium carbonate ])er acre was 

 applied indicated that a larj;e part of the favorable effect of the potas- 

 sium carbonate was due to its alkalinity. Sodium chlorid applied in 

 amounts of 81)0 lbs. i)er acre proved poisonous; when applied in 

 amounts of 445 lbs. it produced considerable increase in yield. 



Magnesium chlorid applied at rates of 445 and 890 lbs. per acre not 

 only decidedly increased the yield, but also increased the amount of 

 potash taken up by the crop. The sodium chlorid did not produce the 

 latter effect. Consequently the sodium salt may b(^ considered to a 

 certain extent as a conserver of potash, while the magnesium salt may 

 be useful in rendering available the insoluble potash compounds of the 

 soil. 



In case of the mustard the results were much the same as with 

 alfalfa, except that the use of sodium carbonate resulted in a decided 

 decrease in yield, and the sodium and magnesium chlorids also proved 

 injurious. 



As regards the yield of potatoes, the hartsalz produced better results 

 than kainit and carnallit, although the percentage of starch in the 

 potatoes was larger in the case of kainit than with the other salts. 

 The total amount of starch produced in case of the hartsalz and 

 carnallit, however, was much greater than with the kainit. 



Comparative tests were made of pure potassium chlorid and potas- 

 sium sulphate. Both salts produced a larger yield than any of the 

 Stassfurt salts, but the percentage of starch in the tubers was no 

 higher. Potatoes fertilized with potassium chlorid contained 15.(59 

 per cent of starch, while those fertilized with potassium sulphate con- 

 tained 16.71 per cent. 



Experiments with various potash salts on a mixture of grasses 

 and leguminous plants (clover) on a light sandy soil, M. 

 Maercker (Jahrh. agr. cliem. Vers. Stat. Halle, 1895, j^P- 16-21). — This 

 is an account of a continuation of experiments begun in 1893. The 

 potash salts used were kainit, carnallit, sylvinit, potash and magnesia 

 sulphate, and a mixture of carnallit and potassium chlorid. These 

 were applied at rates of 533.G and 801. G lbs. per acre, and proved about 

 equally effective in increasing the yield. In each case the potash 

 appeared to be largely exhausted by the first cutting. This was true 

 in case of both the light and heavy applications. The excess of potash 

 in case of the latter appeared to be utilized in the production of a luxuri- 

 ant growth. The results indicate that it is a mistake to suppose that 

 any considerable amount of the potash applied to one crop of hay is left 

 in the soil for succeeding crops. In order, therefore, to get the best 

 result apjdications of potash should be nuide each season. 



Experiments on the influence of crude potash salts upon the 

 consumption of water by plants, ^I. Mai;rcker [Jahrh. ai/r. chcm. 

 Vers. Stilt. Jlalle, IS!)r>, ;>/>. ir>, /6).— Kainit, (tarnallit, and common salt 

 applied at rates of 890 and 1,780 lbs. per acre were compared on whit^ 



