AND SUCH AS ARE RICH IN VEGETABLE MATTER. 383 



or marshy, and full of vegetable matter, as our peat bogs are, lime may- 

 be laid on more unsparingly than under any other circumstances. 

 For in this case, besides the action of the access of water, as above ex- 

 plained, the vegetable matter combines with and masks the ordinary 

 action of a considerable quantiiy of the lime. By this combination, no 

 part of the ultimate influence of the whole lime upon the soil is neces- 

 sarily lost ; in most cases the immediate effect only is lessened, which 

 the same quantity applied to odier soils would have been seen to pro- 

 duce. In favorable circumstances its action is retarded and prolonged, 

 the compounds it forms with vegetable matter decomposing slowly, and, 

 therefore, remaining long in the soil. 



To the exact chemical constitution of the compounds thus formed, 

 as soon as lime is mixed up with a soil rich in vegetable matter, and to 

 the chemical changes which these compounds gradually undergo, it will 

 be necessary to direct our attention when we come to study the theory 

 of the action of lime, as an improverof the soil. 



d. Not only the natural depth of the soil, as already stated, but also 

 the depth to which it is usually ploughed, and to which it is customary 

 to bury the lime, will materially affect the quantity which can be safely 

 applied. A dose of lime which would materally injure a soil into 

 which the plough rarely descends beyond two or three inches, might be 

 too small an application where six or eight inches are usually turned 

 over by the plough. When new soil, also, is to be brought up, which 

 may be supposed to contain no lime, or in which noxious substances are 

 present, a heavier dose of lime must necessarily be laid upon the land. 



3°. Such are the circumstances in which large applications of lime 

 may be usefully applied to the land. In soils of an opposite character, 

 not only will smaller quantities of lime produce an equally beneficial 

 effect, but serious injury would often be inflicted by spreading it too lav- 

 ishly upon your fields. 



The more dry and shallow^ the soil, the more light and sandy, the 

 less abundant in vegetable matter, the more naturally mild its locality, 

 and the drier and warmer the climate in which it is situated — the less 

 the quantity of lime which the prudent farmer will venture to mix with 

 it. It is to the neglect of these natural indications that the exhaustion 

 and barrenness that have occasionally followed the application of lime 

 are to be ascribed. It is only in rare cases, such as the presence of 

 much noxious mineral matter in the soil, that these indications can be 

 safely neglected. 



§ 11. Ought lime to he applied in large doses at distant intervals^ or in 

 smaller quantities more frequently repeated 1 



The quantity of lime which ought to be applied to the land must, as 

 we have seen, vary with its quality, and with the conditions in which it 

 is placed. Hence the practice in this respect necessarily varies in every 

 county and in almost every district. 



But a difference of opinion also prevails among practical men, as to 

 whether that quantity of lime which land of a given kind may require 

 ought to be applied in large doses at long intervals, or in smallquantities 

 frequently repeated. The indications of theory in reference to this point 

 are clear and simple. 



