That this is the true origin of the mosses is rendered fairly certain by the circumstance of works of human art having often been found at the bottom. When Ashton Moss was drained, there were found under the peat a Celtic axe and some Roman coins;[11] and in another part, at the foot of one of the old stumps of trees, a quantity of charred wood, betokening that a fire had once been lighted there. The coins would naturally suggest that some old Roman soldier had had a hand in the kindling, and the well-known fact of the extensive felling of trees by the Romans, both in road-making, and to aid them in the subjugation of the country, has led to the belief with some, that to these people may partially be attributed the origination of the mosses. The trees and scattered branches encumbering the ground, are supposed to have checked the free passage of floods and other water, which, becoming stagnated, gradually destroyed the growing timber, and eventually led to the results described above. Baines (History of Lancashire, iii. 131) says of Chat Moss, that it was originally the site of an immense forest, but was reduced to a bog by the Roman invaders, at a period coeval with the first promulgation of the Christian religion. It would probably be no error to assert with Whitaker, that the whole of the country round Manchester, and not merely the site of Chat Moss, was, at the time of the Romans, covered with trees. One thing is quite certain, namely, that the formation of the mosses is comparatively recent, and probably much within one thousand eight hundred years. They appear to rest universally on a clayey substratum, and it is very interesting to observe that where the peat is wholly removed, for the purpose of fuel, as upon Holford Moss, near Toft and Peover, the clay surface being then laid bare, birch-trees spring up unsown. The seeds of these trees must have been lying there since they ripened, unable to vegetate previously for want of air and the solar warmth. It is quite a familiar phenomenon for plants to spring up in this way from seeds that have been buried for ages, especially on earth laid bare by cuttings for railways and similar works; so in truth it is no more than would be expected in connection with the clearing away of peat, and the restoration of the under-surface. The tree next in frequency to the birch, as a denizen of the old _silva_, appears to have been the oak.