CALCAREOUS MANURES— PRACTICE. 



77 



which depends merely on the efTects of time, operates independently of all 

 other means for improvement that the land may possess ; and its rate, in 

 this experiment, may be fairly estimated by the increase on the piece s q 

 from 1824 to 1828. The increase here, where time only acted, was from 

 12 to21i bushels. But as the corn gathered here was always much the 

 most imperfectly ripened, and would therefore lose the most by shrinking, 

 I will suppose eight bushels to be the rate of increase from time, and that 

 so much of the product of all the pieces should be attributed to that cause. 

 Then to estimate alone the increased or diminished effects of marl, or ma- 

 nure on the other pieces, eight bushels should be deducted from all the 

 different applications, and the estimate will stand thus : 



1824. 



24 1* 



From 800 bushels of marl. 



SOO bushels of marl. 



1000 bush, cow-pen manure 

 1000 bush, stable manure. 



Even the piece covered with both marl and stable manure (w t) shows 

 according to this estimate a diminished effect equal to lO^ bushels ; which 

 was owing to the marl not being able to combine with, and fix, so great a 

 quantity of manure, in addition to the vegetable matter left by its natural 

 growth of wood. The piece w p, marled at 450 bushels alone, has shown 

 a steady increase of product at each return of tillage, and thereby has 

 given evidence of its being the only improvement made in such manner as 

 both judgment and economy would have directed. 



After the crop and measurement of 1832, it was inferred that the separate 

 products of such small spaces could no longer be relied on, owing to the 

 mixture of the surfaces of adjacent parts, necessarily caused by tillage. 

 Therefore the previously omitted parts were marled before the next course 

 of crops came round. 



CHAPTER III. 



EFFECTS OF CALCAREOUS MA^UFvE ON ACID CLAY SOILS, RECENTLY CLEARED. 



The two next experiments were made on another field of thirty acres of 

 very uniform quality, marled and cleared in 1826 arid the succeeding 

 years. The soil is very stiff, close, and intractable under cultivation — 

 .seems to contain scarcely any sand— but, in fact, about one-half of it is 

 composed of silicious sand, which is so fine, when .separated, as to feel like 

 the finest flour. Only a small proportion of the sand is coar.ser than this 

 state of impalpable powder. Aluminous earth of a dirty fawn color forms 

 nearly all of its remaining ingredients. Before being cleared of the forest 

 growth, and ploughed, the soil is not an inch deep; and all below, for many 

 feet, is apparently compo.sed of the like parts of clay and fine sand. This 

 is decidedly the most worthless kind of soil, in its natural state, that our 

 district furnishes. It is better for wheat than for corn, though its product 

 is contemptible in every thing. It is difficult to be made wet, or dry— and 

 therefore suffers more than other soils from both dry and wet seasons, but 



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