624 Professor L. C. Miall, [Feb. 18, 



Between the peat aud the boulder clay there is sometimes fouud an 

 ancient seat- earth, in which are imbedded the mouldering stunij^s of 

 long dead trees. Oak, Scotch fir, birch, larch, hazel, alder, willow, 

 yew and mountain ash have been met with.* Where a great tract of 

 peaty moorland slowly wastes away, the tree stumps may be fouud 

 scattered thick over the whole surface. Above the seat-earth and its 

 stumps, if these occur at all, comes the peat, say from five to twenty 

 feet deep, aud above the peat the thin crust of living heather. 



Every part of the moor has not, however, the same kind of floor. 

 Streams in flood may excavate deep channels, and wash out the gravel 

 and sand into deltas, which often occupy many acres or even several 

 square miles. The outcrops of the sandstones crumble into masses 

 of fallen blocks. Instead of the usual impervious bed of boulder- 

 clay, we may get a light subsoil. The verges of the moor have 

 commonly this character ; they are by comparison dry, well drained, 

 and overgrown with furze, bilberry, crowberry, fern, and wiry 

 grasses; such tracts are called "roughs" or "rakes" in the north of 

 England. A similar vegetation may be found far within the moor, 

 though not in places exposed to the full force of the wind. Even on 

 the verges of the moor there are very few earthworms, and at most 

 a scanty covering of fine mould ; in the heart of the moor there is no 

 trace of either. The Neniatoid worms which are so common in most 

 soils, and easily brought to the surface by j^ouring a few drops of 

 milk upon the ground, seem to bo absent from the humus. Insects 

 and insect larvae are very seldom found in it. 



In a country where population and industry grow steadily, it is 

 rare to find the moor gaining upon the grass and woodland. Wo 

 have to go back some centuries to fi.nd an example on anything like 

 a large scale. The Earl of Cromarty (Phil. Trans. No. 330, p. 296), 

 writing in 1710, says that in 1651 he saw a "firm standing wood'" of 

 dead fir trees on a hill-side in West Eoss-shire. About fifteen years 

 later he passed the same spot, and found no trees, but a " plain green 

 moss " in their place. He was told that the trees had been over- 

 turned by the wind, aud afterwards covered by the moss, and further 

 that none could pass over it because it would not support a man's 

 weight. The Earl " must needs try it," and fell in up to the arm- 

 pits. 



A section through a thick bed of peat will sometimes reveal the 

 manner of its growth. The lower part is often compact, the upper 

 layers of looser texture. It is not uncommon to find by microscopic 

 examination that while the lower part is made uj) entirely of Sphag- 

 num, the more recent growth is due to heather, crowberry, grasses, 

 hair moss and lichens. In some j)laces the whole thickness is of 

 Sphagnum only ; in others there is no Sphagnum at all. Peat formed 

 of Sphagnum only has no firm crust, and from the circumstances of 



* Tn Yorkshire I think that birch and alder are the commonest of tlic buried 



trees. 



