248 Lord Justice Fry [Jan. 23, 



which it is mainly composed, and is highly absorbent of moisture ; 

 whilst the black peat has lost all, or nearly all, traces of the minute 

 structure of the cells, and is not only unabsorbent of moisture, but 

 is impervious to it. In fact, it constitutes an insoluble substance 

 which is said to be scarcely subject to decay, so that it is used in 

 Holland for the foundations of houses, and is found unchanged after 

 ages, and when the buildings have fallen into decay. It is even said 

 to have remained unchanged after three months' boiling in a steam- 

 engine boiler. The broad difference between these two kinds of peat 

 may easily be ascertained by anyone who will subject the two kinds 

 to the action of water. 



If we now take a section of a peat bog, with a succession of 

 forests one above another, the history of the formation will be, I 

 believe, much as follows : — 



We must get a water-tight bottom — sometimes this is a stiff 

 clay, sometimes a pan, i. e. a stratum of sand or gravel made into a 

 solid plate by the infiltration of insoluble iron oxides, themselves 

 often due to decaying vegetable matter. The necessity of this water- 

 tight bottom is well shown by the fact that in places in the Irish 

 bogs where a limestone subsoil occurs the bog become shallow and 

 dry. 



If on this clay bottom or sandy or gravel soil a forest arises, 

 it may flourish for a considerable period, until the natural drainage 

 of the area is stopped, whether by the choking up of the course of 

 the effluent stream, or from the aggregation of vegetable matter, or 

 from the fall in the course of nature of the trunks of the trees them- 

 selves. Everyone who will consider how much care our rivers 

 require in order to make them flow with regularity to the sea — who 

 thinks for instance, of the works in the Thames valley, or in the 

 upper valleys of the Ehine — will see how often and how easily, in a 

 country in the condition of nature, stagnant waters will arise. In the 

 morass thus formed the Sphagnum has grown, years after years, and 

 if it has not destroyed the old trees it has prevented the growth of 

 young ones. The stools of the trees buried in the antiseptic waters 

 of the Sphagnum pools have been preserved, whilst the fallen trunks 

 have, except when preserved by the like circumstance, rotted, and 

 added their remains to the peat which the Sphagnum has been pro- 

 ducing. It has been observed in several places in Scotland, that the 

 underside of fallen trees which would be protected from decay by the 

 tannin of the Sphagnum is preserved, whilst the uj)per side has 

 decayed or rotted away. Year by year the process of decay on the 

 lower parts of the Sphagnum goes on until the water grows shallower 

 and at last disappears, leaving the original morass choked and filled 

 up by the Sphagnum and the plants which it has nourished. On the 

 top of this soil have grown first the heathy and bog shrubs which 

 first succeed the Sphagnum, and in time, as the soil has grown more 

 solid, forest trees. This is our second forest. This first peat deposit, 

 or the lower part of it at all events, having been turned into the 



