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VIII. — On the Old River Terraces of the Earn and Teith, viewed in connection with 

 certain Proofs of the Antiquity of Man. By the Rev. Thomas Brown, 

 F.R.S.E. (Plate IV.) 



(Read 3d January 1870.) 



Introductory. 



No subject of modern scientific inquiry is more important than the series of 

 deposits in which geology comes in contact with the period of human history. 

 This must be my apology for some of the seemingly trivial details contained in 

 the following paper. When these observations were begun, nothing could be 

 further from my thoughts than any reference to the antiquity of man. But I 

 shall perhaps best introduce the subject by simply narrating the way in which 



I was led forward step by step, till the whole inquiry assumed the form in which 

 it is here presented. 



In the autumn of 1863, I spent some weeks at Bridge of Earn, on the estuary 

 of the Tay, and noticed, as every one must, the carse lands lying along the river 

 Earn, from which they rise by a steep escarpment, running on a dead level back 

 to the base of the hills. They were deposited, our recent geological authorities* 

 say, at a time when the land stood lower and the sea higher than now, and 

 are the estuarine mud of that former period. I had no idea of questioning this 

 opinion, or of examining the deposit, but in my walks I was struck by the 

 marked absence of marine fossils. Long ranges of sections were beautifully 

 laid open, and the absence of marine organisms seemed so remarkable that I 

 was led to make a closer examination. In the deposit I found there were two 

 divisions, a lower and a higher, separated by a bed of peat about a foot in 



* It may be enough to refer to a series of papers from 1860 to 1866 in the Journal of the Geological 

 Society of London, by Mr Jamieson, of Ellon, forming one of the most valuable contributions made of 

 late years to Scottish geology, and one frequently quoted and relied on by Sir C. Ltell. I give two 



I I notations : — 



" The land sank again until the sea in most places reached a height of from 30 to 40 feet above 



the present tide-mark The clays and beds of silt forming the carses of the Forth, Tay, and 



other rivers were accumulated." — 1860. Vol. xvi. p. 371. 



" A depression now took place In the valley of the Tay and Forth this old coast-line 



was 25 or 30 feet above the present, but on the coast of Aberdeenshire, not more than 8 or 10. The 

 old estuarine beds or carses of the Forth, Tay, and other rivers were formed, together with correspond- 

 ing shingle beaches and caves along the coast." — 1865. Vol. xx. p. 195. In this paper the deposits 

 of the Earn are specially described. 



VOL. XXVI. PART I. 2 R 



