822 



EXPERIMENT STATION RECORD. 



FERTILIZERS. 



Preservation of barnyard manure, F. T. Shutt (Canada Expt. 

 Farms. Rpts. 1896, pp. 195, 196).— As supplementary to the experiments 

 on tlie deterioration of manure kept for one year in a partially closed 

 shed, an account of which was given in the report of the experimental 

 farms for 1805, p. 42 (E. S. R., 8, p. 880), the author analyzed a sample 

 of the manure collected at the end of the experiment. The fresh manure 

 used weighed 8,000 lbs., the rotted manure obtained weighed 2,G59 lbs. 

 Comparing the results of the analysis of the rotted manure with the 

 average composition of fresh manure, the following results were 

 obtained : 



Comparison of the composition of fresh and rotted barnyard manure. 



8,0H0 lbs. of fresh manure 



2,659 His. of rotted manure (at end of one year). 



Nitrogen. Ph ^? horic Potash 



Pounds. 



41.6 

 23.6 



Pounds, 



24.8 

 19.5 



Pounds. 

 60. S 

 39. 1 



In experiments in which finely ground mineral phosphate was mixed 

 with fermenting manure (at the rate of 50 lbs. of phosphate per ton of 

 manure) and kept in glass jars buried in a manure heap from April 29 

 to August 20 there did not appear to be any "solvent action, or at most 

 a very slight one, on the mineral phosphate exerted by the manure 

 during the process of fermentation." 



Is there a constant relation between the solubility of phos- 

 phatic slag in ammonium citrate and the -weight of the crop pro- 

 duced? A. Petekmann and J. Graftiau (Bui. >$ta. Agron. Gembloux, 

 1898, No. 61, pp. 5-13). — An account is given of pot experiments with 

 11 different slags ou oats followed by white mustard in 1896 and on 

 wheat in 1897. Examinations of the slags used showed that all of 

 them contained more than 1G per cent of total phosphoric acid and 75 

 per cent of fine meal. The solubility of the phosphoric acid in Wag- 

 ner's ammonium citrate solution varied from 37 to 93 per cent. The 

 free lime determined by repeated extraction of 5 gms. of slag with 

 150 cc. of a 20 per cent solution of sugar free from carbon dioxid varied 

 from 0.81 to 5.07 per cent. As the following table of maximums and 

 minimums shows, the citrate solubility varied inversely as the free 

 lime and directly as the silica soluble in mineral acids. 



Relation between, (Urate solubility and free lime and soluble silica in the slags. 



Calcium oxid (free) 5. 67 (max.) 



Silica soluble in mineral acids :i. 24 (min.) 



Citrate-soluble phosphoric acid 37. 60 (min.) 



Per cent. 



0.84 (min.) 



9.27 (max.) 



93.40 (max.) 



