1869.] NICOL PAEALLEL KOADS. 289 



are said to have drained. This is most remarkably the case in the 

 upper valley of the Spey above Laggan. I have already mentioned 

 the great terrace-mound at the lower extremity of Loch Spey, and 

 nearly on the level of the upper line in Glen Roy. Another very 

 distinct terrace is seen near Garviemore, probably not far from the 

 level of the second line. This terrace much resembles the one at 

 Inverlaire near Loch Treig, but is on a different level. There is 

 another similar flat mound near Glen-Shira Lodge, Tvith a line of 

 washed stones on the hillside, evidently marking a former beach-line. 



Still lower down the main valley and in that of the Truim, fol- 

 lowed by the Highland Railway, similar indications of the former 

 presence of the sea are very striking. Kingussie, 762 feet above the 

 sea, is about 80 feet under the lowest Glen-Roy Hue ; whilst Dal- 

 whinnie Inn, 1182 feet high, is 40 feet above the highest. In the 

 space between, marks of horizontal lines and terraces are very con- 

 spicuous. Thus at the north end of Loch Ericht, a little below 

 Dalwhinnie, and nearly on the level of the upper line, there is 

 a great shingle-deposit of round water-worn stones, showing that 

 the sea has long stood at this elevation. Singularly enough, tliis 

 old beach forms the watershed between the Spey and Tay in this 

 place. Another very strongly marked terrace is seen for miles on 

 both sides of the Spey near Kingussie. It is about 820 feet above 

 the sea, and thus rather lower than the third Glen-Roy line (about 

 30 feet). This difference of level is very small, considering that 

 Kingussie is 30 miles from Glen Roy in a direct line, and 15 from 

 Loch Laggan, where the lowest line terminates in the Spean valley. 

 The breadth of this terrace, the flatness of the surface, broken from 

 place to place by deep irregular hoUows with pools of water at the 

 bottom, and the distinct cliff where it meets the slope of the hill, 

 prove that the sea has stood here for a long time. At Loch Gynac, 

 a small lake in the valley behind Kingussie, there are three terraces 

 quite similar to those in Glen Roy, but far inferior in extent. Two 

 of them also, according to some aneroid observations I made, are 

 nearly on the level of the second and third, or upper terraces in 

 Glen Roy. There are other similar indications of the presence of 

 the sea in this vicinity ; but I shall only refer to some distinct traces 

 of horizontal lines on the declivity of the hill forming the south side 

 of the Laggan valley on the Spey. In regard to all these lines and 

 terraces in this district, they appeared to me to show that the water 

 had retired, or the land risen, by sudden starts, as it were, not by a 

 slow, regular, and continuous process. In this they agree with the 

 phenomena of Glen Roy, and thus confirm the view now given of 

 the origin of its Knes. 



The exact coincidence of the hues with certain cols or passes 

 between the valleys has to many appeared an almost insuperable 

 difficulty in the way of the theory of their marine origin. It has 

 been felt as a strong objection to this marine theory, that the 

 sea in its descent should pause three or four times, just at the 

 level of these three or four openings in the hills. It may lessen 

 this difficulty if we consider that the currents from the west. 



