168 [Senatk 



with agricultural chemistry until it had succeeded in analysing correctly 

 a given spot of soil previous to sowing the crop ; analyzing it again 

 after the crop was gathered, and then analyzing the crop itself. Tliese 

 would probably throw more light on what the crop has taken away 

 fioni the soil, and hence would be evident what addition ought to be 

 made to renovate it. Although this appears very simple on paper, yet 

 a little reflection will show, that it is an experiment requiring the greatest 

 care and forethought, as well as numerous trials on similar crops 

 in dissimilar soils, and with various manures to lead to information of 

 the desired weight. But I have seen with much pleasure in some late 

 publications from England, that this idea has also struck some of the 

 agricultural experimenters there, and 1 doubt not that these desirable 

 investigations will now be undertaken. 



It is well known among agriculturists that the use of lime has 

 undergone considerable discussion ; sonie asserting it to be of great 

 value, others having found it of little or none. If lime be added to 

 the manure heaps, one of its chief effects is to set free that substance 

 so indispensable to vegetation, called ammonia ; the odor of this is 

 so strong that any farmer may satisfy himself on the subject by add- 

 ing a spoonful of lime to a little manure. Now, abundance of am- 

 monia is necessary for a crop to grow luxuriantly: suppose a soil 

 formed in a limestone region ; it will of course contain plenty of 

 lime, from the disintegration of the rock of which it is composed. 

 When the farmer's annual deposit of manure is w^orked into the earth, 

 there it always ftnds enough lime to liberate all the ammonia it con- 

 tains. But he. knowing nothing, either of the composition of his 

 soil or of the action of the lime, reads that some farmer at a dis- 

 tance has used lime with great effect, and applies it, thinking it must 

 be a good substitute for manuie ; he is disappointed, and throws the 

 fault on the lime. Take now another soil, for instance, in a granite 

 region, containing naturally a very little lime, which has been annu- 

 ally well manured. The whole of these annual deposits is certainly 

 not exhausted by the ciops which have been taken from the ground; 

 there is no doubt much of it lying decomposed. Lime used freely 

 on a soil like this would prove of the greatest advantage — to use a 

 simple phraseology, it would search out the undecomposed manure 

 and extract its valuable ingredient, ammonia, for the use of the crop. 

 Here, then, the farmer would finfl lime most valuable.* It is, then, 

 generally from ignorance of accompanying circumstances that such 

 ditTerences of opinion arise. 



The practical applications of science to agriculture, however, is 

 yet in its infancy, but every year develops new ideas, and every suc- 

 cessful resuh arising from its application, produces new proselytes 

 to the opinion of its great value, and new students of its powers. 

 England, with all its agricultural energy, is, 1 believe, yet far behind 

 China in the quantity of its extracts of food from the soil, at least 

 if we may judge froji the much denser population which finds sub- 



• It is not intendeil to be asserted, that this is the only, or even the most important ge- 

 neral action of lime on the soil ; we have much yet to leaxn ere we can come to perfecUf 

 satisfactory conclusions on this subject. 



