On the Manuring of Grass Land. 241 



" By means of ammoniaccal salts, a part of the insoluble mineral constituents 

 present in the soil is renderud soluble, and a larger fraction of tlie entire sum 

 of mineral constituents is rendered active, or capable of entering into the ]ilant ; 

 consequently b}^ manuring with ammoniacal salts there is removed from the 

 soil, in the excess of produce reaped the first year, a part of those mineral con- 

 stituents which would have been rendered soluble and available by natural 

 causes in the second year. The soil in the second year is poorer in these avail- 

 able mineral constituents than it would have been had no ammoniacal salts 

 been applied in the preceding year." * 



By the plan recommended we set free silicates and other com- 

 pounds in the heaps, and add them to the fields, so that exhaustion 

 is prevented. I liave recently met with a striking practical con- 

 firmation of the theory here adopted, and it is presented to the 

 farmer as the teaching' of one wliose knowledge was exclusively 

 the result of observation, and who contributed largely to improve 

 British agriculture. The extract is from a pamphlet on farmyard- 

 manure, published in 1828 by the late Mr. Blaikie (the well- 

 known steward to Mr. Coke), which I recently and for the first 

 time met with accidentally at a friend's house : — 



" Much has been said and written upon the subject of the valuable properties 

 of urine, and of the sweepings of farmyards, as manure for grass-land. It has 

 been recommended to collect the whole wash of the farmyard in reservoirs, and 

 to convey it thence into the fields in water-carts ; but this theory should not 

 be reduced to practice unless it is ascertained that the benefit to be derived 

 from the manure so conducted covers the expense. It is a good method (where 

 situation will admit of the practice) to collect the wash of the farmyard into 

 tanks, where a body of water can be thrown into it sufficient to effectually irri- 

 gate some adjoining piece of grass ground situate upon a lower level. It is 

 also an advisable method to throw litter, scourings of ditches, and such other 

 refuse, into the tanks in sufficient quantity to absorb the urine and wash 

 of the yards which run into them. Compost so collected is admirable top- 

 dressing for permanent grass lands, or for young clover layers." — p. 7-8. 



Common salt is included in every manure here recommended, 

 because experience has shown its beneficial action upon grass 

 whenever it has been properly applied, and because the analyses 

 show that grass always contains both its elements, chlorine and 

 sodium. 



The quantity recommended is 1 cwt. per acre, which Is more 

 than a sufficient addition to the natural supplies for the largest 

 crop of grass we can imagine as being reaped from an acre ; and 

 the animal application of this substance is justified by Mr. H. S. 

 Thompson's experiments on the power of soils to absorb manure. 

 He says : — 



* Royal Agricultural Society's Journal, vol. xvii. pp. 301, 302. Vide also my 



Essay on Fermentation of Manure, Royal Agricultural Society's Journal, vol. 

 xvi. p. 323, passim. 



VOL. XIX. R 



