^{page 240 note *} Comrie is a village about twenty-two miles west of Perth, situated in the valley of Strath-Earn, and on the north side of the river Earn, about four miles below the place where it issues from the lake. The remains of a Roman camp on the oppisite side of the river, have made the name of this village very well known to Scottish antiquaries.

^{page 241 note *} Ochrertyre is about four miles E. N. E. from Comrie.

^{page 245 note *} The tract within which the concussions described in this letter appear to have been consined, is a space of a rectangular form, which extends from east to west along the north side of the Earn about 22 miles in length, by a little more than five in breadth ; reckoning the utmost length from about Monzie to the head of Loch Tay, and the breadth from a little south of the Earn northward to the ridge which separates the branches of that river from those of the Almond. The whole of this tract is mountainous, except toward the eastern extremity, where it joins the low country, and on the banks of the river Earn on the south. It is intersected by narrow glens or valleys, the most considerable of which is Glen-Leadnach, where the centre of the concussions seems to be placed. The mineralogy of this part of the country has not hitherto been accurately examined ; but it is known in general, that the stone is the primary schistus, and in some places granite ; that no mineral veins, nor any hot springs, have been found in it, and that no volcanic appearances have been observed. In the valleys, among the mountains, iron ore, of the kind that is called bog ore, is daid to abound. Dr Hutton has remarked, that the line which terminates this tract on the S. E. seems to be nearly the same with that where the primary strata sink under the surface, and are covered by the secondary, or horizontal strata. J. P.