18 MR. T. F. JAMIESON ON THE [Feb. 1906^ 



exposure. The Boulder-Clay has an irregular undulating surface, 

 and varies in thickness, but is not more than a few feet deep where 

 the bottom is exposed. Above it lay a bed of Red Clay, followed by 

 a bed of fine clean-washed sand. Then, on the top of the sand, came 

 the rough gravel containing pebbles of yellow limestone, sandstone,, 

 and crumbs of (Crag) shells. In some places this stuff reached nearly 

 to the top of the cutting ; in others it was covered by a few feet of 

 Red Clay and gravel. The total depth of the section was about 

 16 feet. The chief interest lay in its showing that the pebbly gravel 

 containing debris of Crag-shells forms a member of the Red Clay 

 Series, and that the whole lies above a bed of Boulder-Clay of quite 

 a different hue and character, containing not a vestige of the 

 limestone, sandstone, or shelly debris. This section is near Pitlurg 

 railway-station. 



In some of the projecting parts of the coast the Red Clay is often 

 quite like a Boulder-Clay, being very firm and unstratified, with 

 small stones dispersed through it. This is well seen at present 

 along Peterhead Bay. Close to the south side of the town the 

 shore is formed of low rocks of red granite, which are covered by a 

 mass of hard grey Boulder-Clay, 10 or 12 feet thick, containing 

 stones of gneiss, quartz, and granite. The surface of the rock 

 does not show marks of glaciation, so far as I could see. In passing 

 along the Bay southward, the grey Boulder- Clay is very soon observed 

 to become covered by a mass of Red Clay, which gradually attains 

 a thickness of about 10 feet. It is nearly as hard and firm as the 

 grey clay beneath, and contains a good many stones, some of which 

 seem to have been derived from the Old-Red-Sandstone Conglo- 

 merate. It has all the appearance of a Boulder-Clay, such as would 

 be found in a red-sandstone district. On advancing still farther along 

 the Bay southward, one sees the granite gradually sink out of sight, 

 and the grey Boulder-Clay thin nearly quite away into a mass of 

 coarse granite-rubble. The Red Clay, on the other hand, grows 

 thicker ; and at Invernettie, about a mile south of Peterhead, where 

 the bay curves more inland, the granite and its covering of grey 

 Boulder-Clay have both sunk out of sight, but the Red Clay attains 

 a much greater development. 



The section is not now exposed as it was some years ago, when 

 the tile-work was in full operation, but when best displayed I 

 found it to be as follows. At the base was a mass of fine stratified 

 sand, which seemed to descend below sea-level, but was not much 

 exposed. On the top of this sand was a bed of fine laminated 

 brown clay (what the workmen called leaf- clay), which varied 

 in thickness from 1 to 4 feet. Above this was a mass of clay, 

 attaining in some places a thickness of 15 feet, of a decided red 

 colour; generally of fairly-pure quality, but showing no clear 

 stratification, and having some stones dispersed through it. The 

 top of this bed exhibited an undulating outline, and was covered 

 by an irregular seam of coarser stuff from 6 inches to 3 feet thick, 

 composed chiefly of small debris of gneiss and mica-schist. Above 



