MANURES. 161 



its bulk, and of course more expensive to move. On a tenacious 

 soil tlie muck would probably be better, on account of its 

 producing more lightness and friability. 



I am aware it is a common idea that muck is specially appli- 

 cable to loose, sandy or gravelly soils. But the most beneficial 

 effects that I have ever seen from the application of muck have 

 been on clayey soils — the vegetable matter, on being mixed 

 with the soil, breaking its tenacity, and keeping it sufficiently 

 open and mellow at all times. In England the use of clay is 

 regarded as of so much importance in bringing peat-bogs into 

 profitable cultivation, that great expense is frequently incurred 

 in depositing clay on the surface — the coating being sometimes 

 three or four inches in thickness. 



It is not improbable that even the poorest kind of muck, 

 when divested of noxious principles, which, as before-men- 

 tioned, they generally contain in their crude state, may 

 contribute to the growth of plants by affording carbonic acid. 

 Yet we have known cases where the benefit of applying that 

 from mossy bogs unmixed with any other substance, though 

 well prepared by the action of the atmosphere, was not equal to 

 the cost of digging and hauling it a few rods. The explanation 

 is, that there was carbon enough, or nearly enough, in the soil, 

 and that the muck was destitute of other fertilizing elements. 

 Had there been a deficiency of carbon, the benefit from the 

 muck would probably have been greater. But carbon is not 

 generally a scarce element in soils. 



There seems to be reason in Dr. Dana's idea that the action 

 of alkalies is necessary in many cases to develop the fertilizing 

 elements of muck. This is more particularly applicable to the 

 poorer kinds of muck — such as are obtained from swamps 

 where resinous trees grow, and from mossy bogs. This alka- 

 line action is necessary to destroy noxious acids (acetic, tannic, 

 &c.,) and to bring the muck into a condition in which it will 

 decay faster, and by uniting with oxygen more readily form 

 carbonic acid. Dr. Dana goes so far as to say that, " the 

 power of producing alkaline action, on the insoluble geine, is 

 alone wanted to make peat as good as cow dung," and, " by 

 the addition of alkali to peat, it is put into the state which 

 ammonia gives to the dung." He argues that for all agricul- 

 tural purposes, carbonate of ammonia and white or soda ash, are 



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