1865.] WATSON PAEALLEL ROADS OF GLEN ROY. 11 



being shot out in heaps beneath the half-floating ice-foot. The 

 finer clays and older shell-beds are the produce of the somewhat 

 later and more land-sunken time, when the comparatively cleared 

 surface of the rock and the shrunken glaciers no longer supplied the 

 same mass of debris as before. The gales of spring from the S.W. 

 came to break up the ice of winter where it lay on the level shal- 

 lows, such as the long flat of Glen Spean, east of Loch Treig valley, 

 and piled up the blocks of rock which the ice contained into those 

 strange and monstrous sea-beaches (see Jamieson's map) which have 

 been erroneously described as moraines. And, finally, dependent 

 on the sheltered nature of the locality, on its exposure to the pre- 

 valent winds, on the character of the hill face, on the supply of 

 debris from above, on the extent to which particular spots at the 

 sea-level were already clothed with detritus under the influence of 

 the varying currents pouring backwards and forwards over the cols 

 at the glen heads — perhaps, too, to some extent, acted on by the 

 ice-cake — subject to all these influences the terrace-lines were 

 formed along the slopes. Sometimes they were swept away again 

 almost before formed, or were spared only for later destruction ; 

 but, in the case of the sheltered fjord of Glen Eoy, each terrace in 

 turn was carried down with the subsiding land, and protected from 

 injury below the sea in the quiet of the inland fjord, while the next 

 terrace above it was being formed in its turn." 



That there are some difficulties in the way of the " Marine 

 theory " Mr. Watson does not deny, the greatest, perhaps, being, in 

 his opinion, the marvellous perfection of the Glen Roy terraces 

 when compared with anything similar there or elsewhere. He also 

 discusses two other objections, being all that he thinks need con- 

 sideration. The first of these is, that the horizontality of the 

 "roads " is opposed to the idea of their having undergone sub- 

 sidence and re-elevation ; but Mr. Watson observes that there is no 

 reason to suppose that any disturbance of relative levels should be 

 exhibited when areas of thousands or hundreds of thousands of 

 square miles are undergoing secular oscillations, and he cites in 

 illustration the beach-lines along the Norwegian fjords. The other 

 objection has been urged by Prof. Agassiz as his greatest difficulty 

 in accepting the " Marine theory," namely, that the terraces pre- 

 sent "no traces of organic life"*. Mr. Watson answers this by 

 quoting several examples of Quaternary marine deposits which are 

 also entirely barren of fossils ; and he states that it would be sur- 

 prising if fossils had been found in the Parallel Roads, as he has 

 noticed that there is, from some cause or another, an extraordinary 

 gap, utterly devoid of hfe, so far as we know, between the most 

 recent of the old glacial beds and the very oldest of the recent de- 

 posits. The general character of the Scandinavian Quaternary beds 

 he has found to correspond with that of the Scotch deposits, " and 

 they also agree in this, that while true glacial shell-beds are to be 

 found from the sea-level, and below it, up to 500 feet, or a little 

 more, above it, there they cease altogether. The higher stratified 

 * Eeader, Sept. 3, 1864, p. 301. 



