78 STEVENSON— INTERRELATIONS OF THE FOSSIL FUELS. 



especially where expansion of the bog was by transgression, as is 

 so often observed in plain deposits. The peat itself may be the 

 mur for a new deposit, as where the drying of the upper portion 

 invites invasion by a forest growth, to be destroyed by increasing 

 moisture and return of bog conditions. 



A very notable feature of the mur is the abundance at many 

 places of roots and rooted stumps. This has been observed in all 

 parts of the world, and the instances are so numerous that only a 

 few need be cited as illustrations. Tait'^°'^ states that the mosses 

 described by him cover about 9,000 acres. The lowest part of the 

 peat consists very largely of decayed wood, mingled with some 

 black earth and occasional bunches of heather, better developed than 

 those now growing on the surface of the bog. Innumerable tree 

 trunks are at the bottom, lying alongside of their stumps, which, 

 like the heath bundles, are still fixed in the clay. A considerable 

 portion of the moss has been reclaimed by drainage and by complete 

 removal of the peat. The trees at the bottom are oak, birch, hazel, 

 alder, willow and, in one place, a few firs. In one clearing, 40 

 large oak trunks were found lying by their rooted stumps. These 

 stumps, rooted in the clay, rise about 3 feet and are so little 

 changed that they can be removed only with difficulty. But the 

 stumps of other trees are so badly decayed that little can be said 

 about them except that they are rooted in the underclay. Aiton^"^ 

 has remarked that the suggestion that peat deposits originated in 

 forests is abundantly supported by the very frequent occurrence 

 of trees or roots in the underclay. He never had examined a moss 

 of any great extent without finding on its borders and where the 

 peat had been removed " roots of trees still in the ground with their 

 fangs extended as they grew." Along the river Aven, roots of trees 

 are found under every moss " with their shoots firmly clasped into 

 the earth, where they grew." Geikie^°^ says that in many mosses, 

 the tree stumps are of approximately uniform height and that the 



100 Q Xait, " Peat-Mosses of Kincardine," etc., pp. 228, 269, 271, 272. 



101 W. Alton, " A Treatise on the Origin, Qualities and Cultivation of 

 Moss-Earth," Glasgow, 1805, pp. 29, 33. 



i°- J. Geikie, " On the Buried Forests and Peat-Mosses of Scotland," 

 Trans. Roy. Soc. Edinh., Vol. XXIV., 1867, pp. 379, 381. 



