Mr. Weaver on the 
seems evident from this circumstance, that two and even three suc- 
cessive growths of trees have been observed at different depths in a 
section of the same bog. In these instances, the trees lie horizon- 
tally, frequently crossing each other, and either attached to their 
roots or broken off ; and in the latter case, the stumps usually stand 
erect where they grew. The prostration of trees, however, may to 
a certain extent have acted as an auxiliary in promoting the growth 
of peat bogs. And this prostration appears in general to have 
taken place, either from natural decay, or from the trees, possessing 
little hold of a wet spongy soil, having been subverted by storms. 
This may partly account for trees of all ages being found in the 
bogs of Ireland, whether these bogs be situated in plains, or form 
the immediate cover of high mountain tracts. 
§ 213. That Ireland was once covered by extensive forests, 
even in the most elevated chains, can scarcely admit of doubt; for 
independently of the evidence preserved in the peat bogs themselves 
of the growth of trees, numerous stools of trunks, long since cut 
down, yet remain in most of the mountain districts, which require 
only protection from cattle to produce vigorous shoots. The uni- 
versal destruction of the forests of Ireland, is principally to be 
attributed to the general introduction of iron furnaces, as the most 
profitable mode of consuming the timber, then esteemed a drug of 
little value ; and hence the almost total neglect of copsing those 
tracts in which the woods had been felled. Remains of the ancient 
charcoal hearths are still plainly to be distinguished by their ver- 
dure and level circular surface, scattered over the rapidly shelving 
sides of Glendalough, Glenmalur, and other glens, when we look 
down upon them from a considerable elevation. 
% 214. The marly tracts above mentioned, are distinguished by 
i 
