472 



THE FARMER'S MAGAZINE. 



Surface-soil. Subsoil. 



Moisture when analyzed .... 5.36 3.GG 

 Organic matter and water of 



combination . 25.86 8.79 



Lime 14.30 26.03 



Clay 34.84 56.76 



Sand 19.64 4.76 



100.00 100.00 



" In the chemical analysis of this soil the follow- 

 ing results were obtained ; — 



Surface-soil 

 Moisture when analyzed .... 5.36 

 Organic matter and water of 



combination 25.86 



Oxides of iron and alumina. . 13.88 



Carbonate of lime 14.30 



Sulphate of lime .56 



Phosphoric acid and chlorine traces 

 Carbonate of magnesia .... 1 .04 



Potash 07 



Soda 18 



Insoluble siliceous matter . . 38.75 



Subsoil. 

 3.66 



8.79 

 J0.13 

 26.03 

 Not deter- 

 mined. 



1.67 

 49.73 



100.00 100.00 



" 2,000 grains of this soil and 2,000 grains of sub- 

 soil were mixed with 4,000 grains of the liquid 

 from rotten dung. After 24 hours, the clear hquid 

 was carefully drawn off and filtered. Its original 

 dark brown colour was changed into a pale yellow 

 colour. This soil thus possessed in a high degree 

 the property of decolourizing dark-coloured liquids 

 like the washings of dung-heaps. 



*' In both instances it was thus found that rather 

 more than two-thirds of the amount of ammonia 

 present in these drainings in the form of ammo- 

 niacal salts were retained by a very limited quantity 

 of soil. 



" I have purposely used a large amount of liquid 

 in comparison with that of soil. If, under such 

 conditions, the soil is capable of retaining two- 

 thirds of the whole amount of ammonia present in 

 a liquid like the one examined, it is not too much 

 to expect that no ammonia whatever will be lost in 

 practice by carting manure on the fields in autumn, 

 and spreading it at once. The quantity of soluble 

 ammoniacal matters in a heavy dressing of the best 

 dung does not amount to many pounds, and such 

 a quantity, in relation to the weight of the soil 

 ready to take up ammonia from the manure, is so 

 insignificant, that the most scrupulous may rest 

 satisfied that in a soil containing even a small pro- 

 portion of clay, no ammonia will be lost by dress- 

 ing the fields in autumn. 



" For better comparison sake, I will give the 

 composition of the drainings before and after pass- 

 in^r through soil, and then make a few additional 



remarks, which are suggested by such a com- 

 parison. 



COMPOSITION OF DRAININGS FKOM ROTTEN 

 DUNG. 



1 imperial gallon contains- 



of 



Ammonia (in the form 



ammoniacal salts) 



Organic matters 



Sihca 



Phosphates of lime and iron 



Carbonate of lime 



Sulphate of lime 



Carbonate of magnesia .... 



Chloride of sodium 



Chloride of potassium 



Carbonate of potash 



Before After 



filtration filtration 



through soil. 



19.68 



134.05 



.75 



7.90 

 17.46 



2.18 

 12.83 

 22.85 

 35.25 

 85.27 



6.91 



118.50 



2.38 



1.54 



79.72 



7.92 



6.17 



18.90 



26.44 



4.29 



338.22 272.77 



" It will be observed that this liquid, in passing 

 through the soil, has undergone a striking change. 

 Leaving unnoticed several minor alterations in the 

 composition of the original liquid, I would direct 

 special attention to the very small proportion of 

 carbonate of potash left in the drainings after con- 

 tact with this soil. It will be seen that, out of 85 

 grains of potash contained in the original liquid, 

 no less than 81 grains have been retained by the 

 soil. This is a result of the greatest importance, 

 inasmuch as it shows that the soil possesses in a 

 remarkable degree the power of removing from 

 highly-mixed manuring substances not only am- 

 monia from ammoniacal salts, but also the no less 

 important soluble potash compounds. 



" In some subsequent experiments on a light, 

 sandy, red-coloured, very porous soil, containing 

 only little clay and still less lime, but a good deal 

 of organic matter, its mechanical analysis was : — 



Moisture 



Organic matter and water of com- 

 bination 



Coarse white quartz sand . , 



Fineredsandandalittleclaydeposited 



from water on standing 5 minutes 

 Coarse clay deposited on standing 



10 minutes 



Fine clay deposited from water on 



standing for 1 hour 



Finest clay kept in suspension in water 



after standing longer than 1 hour 



3.45 



13.94 



47.00 



19.82 



2.82 



6.30 



6.67 



100.00 



Through this soil a gallon of the drainage from 

 fresh mixed farm-yard dung was passed, when the 

 results were obtained which are given in the follow- 

 ing table ; — • 



