Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/914

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664 proceedings of the GEOLOGICAL sociEir. [June 22, size. In most instances the roots of the trees are found extending far down into the subsoil beneath ; and when the overlying peat is removed, about 2 feet of the stem is found left standing above the sur- face of the ground in which it grew. Submarine forests are found, more or less, all along the Lancashire coast, as in North Cheshire — and when not seen, are present beneath the sea-sand, occurring sometimes at Southport 80 feet below high-water mark. The sub- marine peat and forest is everywhere connected with the peat and submerged forest of the lowlands (or " broads," as they would be called in some districts), running under the sand dunes which fringe the coast, in a belt varying from a half to nearly four miles in breadth, and often reaching an elevation of nearly 100 feet above the level of the sea. To the north-east of Southport, towards the river Douglass, the site of the old lake, Martin-Mere, called by Camden " the biggest mere in Lancashire," is covered with very thick and dense peat, resting on the Cyclas-iAaj. Its waters appear to have been bounded to the north by the hill of Boulder-clay, masked at the bottom by Shirdley-Hill sand, near Tarleton, referred to in the description of that sand, the position of which is traced on fig. 3. The lake contained in the sixteenth century 3400 acres, but was drained in 1692 by Mr. Thomas Fleetwood, who spent an enormous sum of money in doing so. While the excavations were going on, eight canoes, each hewn out of a single tree, were found; one of them, I believe, is in the British Museum. According to Leigh's ' Natural History of Lancashire,' published in 1700, one of the canoes had iron plates on it. He also relates the finding of great quantities of fir stocks and fir-apples. The fir trees found under the moss, then as now, were so bituminous as to be used as candles by the neigh- bouring inhabitants. Leigh also mentions that, under the moss, distinct plantations of birch, oak, ash, and pine were found, that had evidently been planted. Some trees that I have observed dug up from the moss over the site of this lake certainly appear to have been cut down by some blunt implement, possibly a stone axe ; and many of the oak trees in the submarine forest near the mouth of the Alt appear to be placed in right lines at equal distances. But the bases of these have every appearance of having become gra- dually rotten, owing to the obstruction of drainage causing the rise of water, in which peat began to form, and into which the trunks were afterwards blown by powerful westerly and south-westerly winds, to which the half-rotted stems formed an easy prey. Everywhere in West Lancashire the heads of the buried trees generally lie to the north-east, especially when the trunk is not entirely separated from the roots. The trees dug up from the mosses are generally of a black colour ; and the wood has often acquired a considerable density, and is occa- sionally used for furniture and house-fittings. The trees at the base of the peat at Bimrose Brook, the mouth of the Alt, Formby, and near Southport are chiefly oaks and pollard ashes, in Croston and Marton Mosses chiefly oaks and yews, and in Lytham Moss oaks and