522 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Feb. 24, 



regularity wherever the rock sits low, and that these fine strata are 

 covered in some places by extensive masses of coarse gravel and 

 shingle, and in others by a clay or earth full of boulders of many 

 kinds, often of large size, and sometimes striated and grooved in a 

 singular manner. It has also been shown that great boulders occur 

 on the surface of the gravel-ridges, and, according to the accounts 

 of workmen, occasionally imbedded in their interior, although I have 

 not observed this latter fact myself*. 



These stratified masses have been found resting on Old Red Sand- 

 stone conglomerate at Millden, and on gneiss and mica-slate along 

 the sea-margin of Slains ; and no clear instance along the coast has 

 occurred to me of any mass of coarse stuff, containing large boulders, 

 lying beneath them ; nor have any large blocks been seen by me 

 imbedded in the fine strata themselves. These are evidently the 

 remains of an old sea-bottom of the later Tertiary period, — the 

 laminated clay and sand having accumulated in the deeper troughs 

 of the ancient coast, where they were beyond reach of the surface- 

 agitation produced by the winds. 



In the parishes of Slains and Cruden there are many knolls and 

 ridges of water- worn shingle and gravel, which I have found in various 

 places to contain broken marine shells. Perhaps the most remarkable 

 of these are the gravel-ridges beside the Loch of Slains, locally known 

 by the name of the Kippet Hills. They vary in form and size, but 

 generally rise to the height of about 30 or 40 feet above their base. 

 The sides are commonly steep, and their summit or ridge often so 

 narrow that two carts could scarcely pass each other on them, while 

 their breadth is such that a person standing on one side can easily 

 pitch a pebble quite over them. In these features they would seem 

 to resemble the Eskars of Ireland, the Kaims of the south of Scot- 

 land, and the Osar of Sweden, concerning the origin of all which 

 there has been some discussion. 



Our Kippet Hills can be traced, with hardly any interruption, 

 for a distance of beyond two miles, in a tortuous, curving, or zigzag 

 line without any definite direction. They are connected also with 

 other gravel- deposits in the district ; and their extent and relations 

 are obscured to some degree by a deposit of red clay which covers 

 them in many places. 



Fig. 4. — Diagram showing the Red Clay covering, and filling up the 

 hollows of the Gravel-ridges at the Kippet Hills. 



a. Clay. b. Gravel. 



* I am inclined to think that the gravel on the top of which these erratic 

 hlocks lie is of older date than the gravel covering the stratified beds at Aberdeen 

 and elsewhere. It may belong to the same period as the gravel of the Kippet 

 Hills. 



