FERTILIZERS. 31 



phosphatic materials on moor soils may be considered equal, and that the residual 

 effect of the fertilization with Wiborgh and Thomas phosphates was more pronounced 

 than that of superphosphate. 



Experiments with different potash salts. — The results of earlier experiments were cor- 

 roborated, showing that the different potash salts on the market may he considered 

 of equal value for grain crops, legumes, or pastures on moor soils. The potash salt 

 that can be bought at the lowest price per unit of potash is therefore to be preferred, 

 since the cost of freight is of importance in determining the price of the fertilizer in 

 local markets, the 37 per cent potash salt and the muriate being generally preferable. 

 This is especially true in the case of fertilization of potato land. The high-grade 

 salts produced the largest crops of potatoes, and the starch content of the j >ota toes 

 was 1 to 2 per cent higher in the case of plats to which such salts had been applied 

 than from fertilization with kainit. 



On i)te action of lime and soil amendments <m barren moor sails. — Plat experiments 

 were conducted with soil from a piece of moor land which did not normally grow 

 any crops, and which consisted in its upper layer of partially decomposed Erio- 

 phoruni plants. It is shown that such soils can be made to produce normal crops of 

 oats, peas, etc., through liming, admixture of sand or clay, and proper fertilization 

 with phosphates, potash, and even some nitrogen. Barnyard manure also produce 1 

 good effects and is of value for the purpose of facilitating the decomposition of the 

 organic matter in the soil. The improvement in the quality and the yields of the 

 crops harvested on plats receiving different treatment was striking. — f. w. woll. 



Some lessons learned from experiments with fertilizers, W. Saunders 

 (Proc. Soc. Prom. Agr. Sri., 1904, pp. 105-112). — A brief general discussion of the fer- 

 tilizer requirements of plants and a summary account of the experiments with fertil- 

 izers made at the experimental farms at Ottawa since 1887. 



The so-called statistical method of making field experiments with fertil- 

 izers and calculating the results, T. Pfeiffer (Mitt. Landw. Inst. K. Univ. Bres- 

 lau, 2 (1904), A T o. 4, PP- 647-682, fig. 1). — This is a controversial article replying to 

 one by Dafert (E. S. R., 15, p. 130), which explains the doubtful reliability of field 

 experiments ordinarily conducted by farmers, and the need of greater accuracy in 

 such experiments if they are to yield results of scientific and practical value, refer- 

 ence being made to the author's plan for securing greater interest in this subject by 

 offering a series of premiums (E. S. R., 13, p. 726). 



The main portion of the article, however, is devoted to a detailed discussion of 

 the reliability of conclusions based upon averages of the results of a large number of 

 individual experiments — the so-called statistical method advocated by Dafert — the 

 general tenor of this discussion being that more reliable and useful results may be 

 obtained by increasing the accuracy of individual experiments rather than by 

 increasing the number of cooperative experiments as ordinarily made. 



Plant food and use of fertilizers, A. L. Kxisely ( Oregon Sta. Bid. 79, pp. 40). — 

 A popular discussion of this subject, including directions for making fertilizer experi- 

 ments and preparing mixtures for different crops. 



A contribution to the knowledge of metaphosphates, F. Warschauer (Ztschr. 

 Anorgan. Chem., 36 (1903), pp. 137-200; alts, in Bid. Soc. Chim. Paris, 3. ser.,32 

 (1904), No. 11, pp. 653-655). — This article gives a critical historical review of investi- 

 gations on this subject, and describes the distinctive characteristics of the various 

 modifications of metaphosphoric acid, including monometaphosphates which are 

 uncrystallizable, insoluble salts; tnmetaphosphates which are easily crystal iizable 

 and soluble, but are not precipitable; tetrametaphosphates which are crystallizable, 

 soluble, and precipitable; and hexametaphosphates which are amorphous compounds, 

 the alkaline salts giving with the salts of the alkaline earths and heavy metals pre- 

 cipitates which are either flocculent or gelatinous. The preparation and chemical 

 behavior of various salts of these acids are discussed. 



