258 CALCAREOUS MANURES— APPENDIX. 



to no profitable search for causes, or for truth. The children of the first 

 settlers of the west have grown up among prairies ; and when another 

 century shall have passed, and our frontier settlements shall have reached 

 the base of the Rocky Mountains, it may begin to be believed there, that 

 the forest state is rarely known to nature, and is only produced by the 

 labors and care of man. So the Bedouin Arab thinks the world is made of 

 naked sand — and the Shetlander's world is of wet peat. 



Of course these general remarks apply to those who are acquainted only 

 with some one region of the world, and who have not been informed of 

 others by books, any more than by travel. Among the more learned, there 

 has been no lack of causes assigned for these opposite appearances ; but 

 they are such as to show a strange disregard of all the requisites of sound 

 reasoning, and of accurate investigation. Any reason that was first ad- 

 vanced, however insufficient, however absurd, seems to have been readily 

 admitted, and to have passed current from one traveller, or writer, to ano- 

 ther. Thus, to the annual fires alone has been attributed the destruction 

 of trees, and the formation of the great prairies of the west ; and this cause 

 has been deemed sufficient by both the learned and the ignorant. The ob- 

 jection to it is, that all the Atlantic slope was burned over as often as the 

 west, before the settlement of the country, and in the former (at least east 

 of the mountains) not one acre of prairie had been produced. 



Philosophical writers have maintained supposed causes of the destruction 

 of tlie fi3rests which formerly covered England, which are very plausible 

 when considered alone. But precisely similar causes have been operating 

 long and generally in this country, and our forests not only do not decay 

 and die, but continue to defy every agent of injury, except the thorough use 

 of the axe and plough. Even where long continued tillage has the most ef- 

 fectually eradicated the natural and original forest growth, if the impover- 

 ished land is merely let alone for thirty years, it will (in most cases) be 

 better covered with a new growth of trees, than the utmost care could raise 

 in England. Examples of the facts and reasoning referred to are presented 

 in the following passage from Davy. " In instances where successive gene- 

 rations of vegetables have grown upon a soil, unless part of their produce 

 has been carried off by man, or consumed by animals, the vegetable matter 

 increases in such a proportion, that the soil approaches to a peat in its 

 nature ; and if in a situation where it can receive water from a higher dis- 

 trict, it becomes spongy, and permeated with that fluid, and is gradually 

 rendered incapable of supporting the nobler classes of vegetables. 



"Many peat-mosses seem to have been formed by the destruction of 

 forests, in consequence of the imprudent use of the hatchet by the early 

 cultivators of the country in which they exist : when the trees are felled in 

 the out-skirts of the wood, those in the interior are exposed to the influence 

 of the winds ; and having been accustomed to shelter, become unhealthy, 

 and die in their new situation, and their leaves and branches, gradually de- 

 composing, produce a stratum of vegetable matter. In many of the great 

 bogs in Ireland and Scotland, the larger trees that are found in the out-skirts 

 of them bear the marks of having been felled. In the interior, few entire 

 trees are found; and the cause is. probably, that they fell by gradual decay; 

 and that the fermentation and decomposition of the vegetable matter was 

 most rapid where it was in the greatest quantity." — [_Lec. 4.] In Virginia 

 no one forest tree has been known to die, or even to decline, from being 

 exposed in the manner above described as so fatal : and such effects being 

 produced in England would only prove that the soil was unfavorable to trees, 

 and their life therefore feeble and sickly, and ready to yield to any new and 

 considerable cause of injury. 



