98 nEpOure) 857. 
soon become sufficiently matted together so as to be capable of bearing up the other 
plants enumerated as forming this variety of bog. It was further stated, that although 
Sphagnums constitute a large portion of this substance, without the aid of phanero- 
gamic plants the formation of bog could not go on at nearly so quick a ratio as it does. 
In the absence of all trustworthy experiments on the growth of bog, the rate of 
increase could not be well ascertained, but holes out of which turf had been cut had 
been observed filled up with soft vegetable matter, to the depth of 1 foot in five years, 
which, if supposed to be ultimately compressed into one-fourth part of that bulk, 
after being solidified, as near an approach as can be made to the rate of increase of 
bog at the present day might probably be reckoned on. In limestone districts, where 
the larger species of Chara abound, whose stems and branches are always thiekly 
encrusted with calcareous substances, the deposition of matter takes place faster than 
it does where those plants are not so common. The debris resulting from Chara 
hispida alone, where it grows freely, will soon fill up a shallow pool, so that plants 
higher in the scale of vegetation can grow on it. According to the Report of the 
Commissioners appointed to report on the nature and extent of the Lrish bogs, up- 
wards of a million of English acres are covered with red and brown bog, more than 
two-third parts of which are westward of the river Shannon. 
The variety called black or turbary bog was next considered in detail, which is 
the most valuable for fuel, owing to the great quantity of woody matter it contains. 
This variety is supposed to have been formed on the sites of ancient forests, which 
either spread continuously over large portions of the country, or skirted the margins 
of morasses, as is evident from the large quantities of prostrate trunks of trees and 
their roots, frequently in situ, which are found in it. The kinds consist chiefly of 
Pinus sylvestris, Quercus robur, Betula alba, and Alnus glutinosa, though large quan- 
tities of yew, Taxus baccata, and some mountain ash, are also found in particular 
districts. The roots of the oaks are generally nearest the margins of the bogs, resting 
on the clay or marl bottoms ; whilst the Scotch firs occur further towards the centre, 
and rest on several feet of peat, thus showing that a considerable accumulation of 
that substance must have taken place before they vegetated on it. These roots are 
frequently found one above the other, where they have grown, which has led some 
to suppose there have been several consecutive and distinct epochs of growth, and 
that some species of the trees which formed them are not now natives of Ireland. 
This hypothesis was not considered correct, but rather, that by the gradual growth 
of the bog, matter accumulated and covered the first tier of roots, and the seeds of 
contiguous trees, on falling and vegetating above them, grew and formed in their turn 
another tier, and so on up to the present surface, as a few of the trees of those 
ancient forests which once covered so large a portion of Ireland still exist on the Earl 
of Arran’s property in the County Mayo at the present time. 
After the plants which form this variety of bog were enumerated, the kind called 
mountain bog was next considered, which sometimes accumulates to a great depth 
on the tops of mountains, at elevations varying from 1000 to 2000 feet. The Sphag- 
nums do not enter so largely into the composition of this kind, but their place is 
supplied by the grey moss, Racomitrium lanuginosum. The conclusions Mr. Moore 
has come to on this subject are the following; namely, that so far as proofs exist, the 
same plants which are now forming the bogs of Ireland have done so from the bottom 
upwards, though probably at different ratios, as drainage has increased, and that all 
the species are still m existence in Ireland which have ever formed any part of them. 
These formations he considers to be of a more recent date than the glacial epochs of 
geologists, with probably the exception of that at Lough Neagh, which may have been 
anterior to that period ; but he thought it would be very hazardous to state the species 
which formed the fossilized wood found there. 
On the Importance of a thorough understanding of the Root Principle in the 
Cultivation of Trees. By N. Niven, Landscape Gardener and Garden 
Architect, Sc. 
Success in connexion with the cultivation of trees, but especially fruit-bearing trees, 
is unquestionably of the utmost importance as far as matter-of-fact result goes in 
the production of fruit, and therefore the desirableness of a thorough understanding 
ee 
