POWERS OF SOILS. 353 



sorbing ami retaining water, bj the amount of peaty matter which it contains, subject to 

 modification by it* fineness. 



That it is tin- vegetable or organic matter contained and intimately combined in soils 

 which u r i\c them in the main their powers, is supported by the fact, that when it is 

 destroyed or removed bj ignition, very little difference exists among them as it regards the 

 powers in question. This statement is confirmed when experiments are made upon marl 

 and clay first in their natural state, and afterwards when ignited. In the condition to 

 which they are brought by this process, they differ but a trifle from each other, as it re- 

 gards the amount of moisture they will absorb in equal times and under similar conditions. 

 It seems, that after burning, the different kinds of soils are brought down to the same 

 standard. Thus, in fifteen samples of soils selected from different districts, some of which 

 were clay and sand, together with peat and marl, on being ignited, they absorbed nearly 

 equal quantities of moisture in equal times : they at most differed only between one and 

 two grains in the amount of water which they absorbed. Two hundred grains of soil were 

 selected for these experiments : they were first moistened with water, till perfectly imbued 

 with it, and, in four hours, they were weighed. This operation was repeated at equal 

 intervals, for many times in succession, and always with the same results ; the peat, or 

 nearly pure vegetable matter, scarcely losing any- water in the course of a few 7 hours, 

 while sand would lose almost all its water, and become nearly dry. After they were 

 ignited, however, they dried sensibly at the same rate ; or when left to absorb moisture 

 after undergoing this process, the sand absorbed nearly as much water as the marl or clay, 

 or the common soils which had been burnt. 



From the foregoing statements, it is evident that soils ought not to be subjected to the 

 process of paring and burning, without special reasons. If there is no objection to burning, 

 on the score of the loss of organic matter, together with a loss in its power of absorbing 

 moisture, then the process will be followed with advantageous results ; for it is unques- 

 tionably true that the mineral or organic matter is more soluble in consequence of having 

 been ignited. Sandy soils, and all the varieties of loams, are rarely improved by burning. 

 When all the vegetable matter is burned ofl", they must necessarily be injured. So, on 

 the other hand, the addition of finely divided vegetable matters, if it served no other pur- 

 pose in soils than to aid and assist in the absorption and retention of moisture, this purpose 

 itself would be quite an important one, and worthy of being secured. Water, in due 

 proportion, must always be regarded as one of the essential elements of a good soil : it is, 

 as it were, the moving power. In this light it would be regarded, if it was merely the 

 medium for transmitting nutriment through the body of the vegetable ; but it is important 

 in other respects, and hence growing plants must have a supply, or else they will suffer 

 or die, according to the degree in which they are deprived of this element. 



[Agricultural Report.] 45 



