Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/135

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of Devonshire and Cornwall.
123

and the other actinolite. Both had been given to him as having been found on Dartmoor.

From Launceston to Bodmin the distance is twenty miles, and between these towns, the highest part of the county of Cornwall intervenes. In the course of this tract of country, we quit, and again enter upon the grauwacke formation. It is exactly at the distance of seven miles and a quarter from Launceston, that it is lost at a height of nearly eight hundred feet above the level of the sea: the nearest village to this place is called Five Lanes. Here the grauwacke is succeeded by a granitic plain, where several rivers, flowing to the right and left, have their source: the Inny, the Fowey, the Camel or Alan, &c.

Brown Willy and Rough Tor do not rise much above their base, not more than other hills of much less absolute height, which are seen in the horizon. The grauwacke is again found exactly at the fourth mile stone from Bodmin, very near Mew London Inn, at a height, which upon that side of the chain appeared to me considerably greater than upon the northern side, but I was not able to determine the point more accurately. The land afterwards falls with a rapid descent to Bodmin, which is only one hundred and eighty eight feet above the level of the sea. The soil of that granitic ridge is boggy, and quite like that of Dartmoor Forest.

From Bodmin to Truro, by the Indian Queen and St. Michael, is twenty-two miles: the grauwacke formation continues the whole way, becoming more slaty as we approach Truro, that is to say, as we get lower down. It then very nearly resembles clay-slate. The most elevated point on this road, and from which the whole of the Bristol Channel may be seen, is in the neighbourhood of St. Michael. From that place to Truro, the vegetation is very luxuriant, but from St. Michael to the Indian Queen, and from thence to within three