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layer of dung, and on that a layer of earth, and so alternately 

 till the pile is elevated a foot or two above the level of the 

 ground, watering each layer of earth with a strong solution of 

 saltpetre this should be left undisturbed for six months. When 

 this compost is moved, it will be found wholly converted into 

 earth, presenting no trace of the dung. 



Guano, like farm-yard dung, is variable in its composition. 

 It is the dung of birds which feed on fish, and consists prin- 

 cipally of salts of ammonia and phosphates, with a little soda and 

 potash. Attempts are being made to produce an artificial guano 

 by a mixture of the mean of the various salts which it con- 

 tains, which shall be more uniform in character. In using these 

 concentrated saline mixtures, it is hazardous to drill them in 

 with the seed, as there is a danger of their killing it during 

 germination : they should be used as a top-dressing, and sewn 

 by hand with care, so as to distribute it as equally as possible 

 over the plot of ground. 



LOAM is a yellowish or brownish kind of clay, sometimes con- 

 taining a considerable proportion of sand. It occurs in immense 

 beds, and is found in almost every part of the world. 



MANURE. This term is applied indiscriminately to all sub- 

 stances which are known from experience either to enrich the 

 different soils, or contribute in any other way to render them 

 more favorable to vegetation. 



In an agricultural point of view, the subject of manures is of 

 the utmost importance. To correct what is hurtful to vegetation 

 in the different soils, and to restore what is lost by exhausting 

 crops, are operations in agriculture which may be compared to 

 the curing diseases in the animal body, or supplying the waste 

 occasioned by labour. 



Rotted dung is very much superior in imbibing and retaining 

 water to that which is fresh, unfermented, or beginning to 

 ferment. The quantity of humic acid is considerably greater in 

 rotted than fresh dung, and it approaches nearer to the best 

 leaf mould or virgin loam. 



Lime should never be applied with animal manures unless they 

 are too rich, or for the purpose of preventing noxious effluvia : 



