30 



A DISCOURSE 



BOOK I. trees and woods, (which hinder the necessary evohtion of this superfluous 

 "^^f^ moisture and intercourse of the air,) render those countries and places 

 more subject to rain and mists, and consequently unwholesome, as is 

 found in our American plantations, as formerly nearer us in Ireland; both 

 since so much improved by felling and clearing these spacious shades, 

 and letting in the air and sun, and making the earth fit for tillage and 



be used as such, -where it can be had without much expense. By increasing the quantity 

 of clay, it will make an excellent compost for a light sandy soil ; but to make the ground 

 fertile, woollen rags, rotten dung, or any oily manure, should be incorporated with it some 

 time before it is laid on. It is the opinion of some, that lime enriches the land it is laid 

 upon, by means of supplying a salt fit for the nourishment of plants ; but by all the expe- 

 riments that have been made upon lime, it is found to contain no kind of salt. Its opera- 

 tion therefore should be considered in a different light ; by the fermentation that it induces, 

 the earth is opened and divided, and, by its absorbent and alkaline quality, it unites the 

 oily and watery parts of the soil. It also seems to have the property of collecting some- 

 thing from the air, but with which we are not yet sufficiently acquainted. From viewing 

 lime in the light of assimilating oil and water, it is probable that it tends to rob the soil of 

 its oily particl-es, and in time will render it barren, unless we take care to support it with 

 rotten dung, or other manures of an oily nature. As light sandy soils contain but a small 

 portion of oleaginous particles, we should be extremely cautious not to overdo them with 

 lime, unless we can at the same time assist them liberally with rotten dung, woollen rags, 

 shavings of horn, and other manures of an animal kind. Its great excellence, however, 

 upon a sandy soil, is by mechanically binding the loose particles, aqd thereby preventing 

 the liquid parts of the manure from escaping out of the reach of the radical fibres of the 

 plants. Upon clay the effect of lime is different ; for by means of the gentle fermentation 

 that it produces, the unsubdued soil is opened and divided : the manures laid on readily 

 come into contact with every part of it ; and the fibres of the plants have full liberty to 

 spread themselves. It is generally said that lime answers better upon sand than clay. — 

 This obsei'vation will undoubtedly hold good as long as the farmer continues to lime his 

 clay lands in a scanty manner. Let him double the quantity, and he will then be con- 

 , vinced that lime is better for clay than sand. It may be justly answered, that the profits 



will not admit of the expense. I agree. But then it must be understood that it is the 

 application, and not the nature of the lime, that should be called in question. Clay, well 

 limed, will, after a time, fall in water, and ferment with acids. Its very nature is changed. 

 Under such agreeable circumstances, the air, rains, and dews, are freely admitted, and the 

 soil is enabl ed to retain the nourishment that each of them brings. In consequence of a 

 fermentation raised in the soil, the fixed air is set at liberty, and in that state of activity it 

 becomes an useful instrument in dividing the tenaceous clay. However, let the farmer 

 who uses much lime for his clay lands, be instructed to manure them well, otherwise the 

 soil will become too hard to permit the roots of the plants to spread themselves in search 

 of food. It is the nature of lime to attract oils, and dissolve vegetable bodies. Upon these 

 principles we may account for the wonderful effects of lime in the improvement of black 



