626 EXPERIMENT STATION RECORD. 



in 2 per cent ammonia. To tbe amniouiacal solution, wliicli sliould 

 amount to about 100 cc, 15 cc. of magnesia mixture is added, drop by- 

 drop, witli constant stirring, the beaker covered with a watch glass, 

 and allowed to stand 2 hours. The ammonium magnesium precipitate 

 is collected on a fdfer of known ash content, washed with 2 per cent 

 ammonia, dried, incinerated over a Bunsen burner 30 to 40 minutes, 

 and ignited iu a Rossler oven for 2 minutes, cooled, and weighed. The 

 method and reagents here recommended are substantially identical 

 with those already described by the author,' except that in the method 

 here proposed no account is taken of the basicity of the substance 

 examined. 



The fertilizing value of the phosphoric acid of bone, Ulbkicht 

 {Agr. (Jhtm. Vers. Stat. Bahme; abs. in Chem. Centbl., 1894, II, No. 10, 

 p. 803). — Experiments in pots in the greenhouse showed that the 

 amounts of available phosphoric acid and perhaps of the other ferti- 

 lizing constituents naturally present in the soil as well as the other 

 properties of the soil have a very great influence on the action of the 

 l)hosphoric acid of bone meal. The soils experimented on were partly 

 natural, slightly loamy sand and partly artificial soils, consisting of 

 quartz sand and kaolin. All pots were liberally fertilized with nitrate 

 of soda and potash, one series receiving superphosphate and the other 

 bone. Taking the dry substance produced in pots receiving 0.132 gm. 

 of phosphoric acid as 100, the ratios of production during different 

 years of an equal amount of idiosphoric acid in form of superphosphate 

 were as follows : 



1890. Light soil, long iTnder culture 110 



1891. New soil poor iuiiliosphoric acid 123 



1892. Quartz sand and kaolin with trace of P-jOs 394 



1893. Soil freed from phosphoric acid 124 



The results indicate that iu soils not entirely devoid of phosphoric 

 acid and not of extremely abnormal properties, both steamed and 

 un steamed bone of proper fineness produced very favorable results, 

 even when applied in the spring, provided the soil was not deficient 

 in moisture. In soils deficient in water very different results were 

 obtained with all kinds of bone meal, but it appeared that the results 

 were more unsatisfactory the coarser the bone. 



The -water-soluble combinations of phosphoric acid in super- 

 phosphates, J. Stoklasa {Landtc. Vers. Stat., 45 {1894), No. 3 and 4, 

 pp. 161-172). — This is a continuation of work previously reported in 

 the same journal (38 (1891), pp. 197, 401; and 42 (1893), pp. 439-457; 

 E. S. R., 2, pp. 611, 757; 5, p. 520), and relates to the action of calcium 

 carbonate and calcium sulphate in the soil and in superphosi)hates. 



iChem. Ztg., 18 (1894), No. 61, pp. 1153, 1154 (E. S. K., 6, p. 370). 



