Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/337

 Having passed Glen Turit, the three lines now become distinct and well marked on the right side, where the hill is covered with a thick alluvium: on the opposite side they are also distinct, although here and there slight appearances of irregularity, and supernumerary marks occur. The bottom of the glen continues to exhibit an many of them being objects of general curiosity, even when not particularly connected with this subject year.

Whatever doubts we may have respecting the general value of the method by which the elevation of the upper lane of Glen Roy was ascertained, I must here remark that this principal measurement receives confirmation, to a certain extent at least, by comparison with the height of that land which is the common division of the Truim and the Garry. This point has been found by levelling to be 1460 feet, and it appears probable from comparing the course of the former river and that of the Spey to their common junction, that the source of the Spey cannot be materially different in elevation; a circumstance confirmed by the barometric observations. The other measurements in the table scarcely admit of any material errors.