igo THE BOOK OF NATURE STUDY 



As decay proceeds the peat gets more and more solid, until brown 

 coal or lignite is formed, and finally coal, in which the original 

 woody structure is not perceptible to the naked eye, although 

 sections under the microscope may show spores, fibres, etc. 



Peat is not often formed in tropical regions, for decomposition 

 goes on too quickly to allow of an accumulation of vegetable 

 remains ; where, however, plant remains accumulate more rapidly 

 than they can be decomposed, the formation of peat begins ; 

 and, once begun, generally proceeds quickly owing to the peaty 

 acids that are formed and have no opportunity of draining away. 

 Anything which hinders drainage and promotes stagnation helps 

 in the formation of peat. When plants at the edge of a pond 

 begin to grow inwards ; or a spring is dammed up by marshy 

 plants, circumstances arise favourable to the formation of peat. 

 Where a district is well drained, peat cannot be formed. The 

 surface of a peat-bog varies very much. Sometimes it is green 

 with living moss ; it may be brown or even black. The moss 

 that is of most frequent occurrence in peat-bogs is Sphagnum, 

 which is called Bog Moss on that account. Others mosses may be 

 found : the peat in the fens of Lincolnshire is formed mainly of 

 Hypnum fluitans, and in the ancient peat beds of Scotland, with 

 Arctic floras, no traces of Sphagnum have been found. It is, how- 

 ever, the chief constituent of recent peat in Ireland, Scotland, 

 and England. 



In peat-bogs remains of trees may be seen, and at first sight 

 it may be difficult to realise that the Bog Moss can have had 

 anything to do with the fact of trees being buried in peat-bogs. 

 It is suggested, however, that the immense quantity of water which 

 this moss is capable of holding has caused the roots of the trees 

 to rot and eventually to be blown down. Then various Fungi 

 and Mosses would grow over them, and in time the trees would 

 be completely buried in the bed of peat, and add considerably 

 to its thickness. 



Peat is not being formed to any great extent at the present 

 time ; in many parts it is in a state of denudation. If the bog 

 is on a hillside, channels and furrows begin to appear in the peat, 

 and may be even twelve feet in depth. As the channel becomes 

 widened by the stream cutting its way down, the roots and stems 



