216 



boulder-clay, indicated less violence and less extent of agitation and 

 movement in the waters. 



(4.) The deposits of clay prove that general tranquillity or calm- 

 ness succeeded the above periods. From the discovery of terres- 

 trial remains, both animal and vegetable, in this deposit, it is ob- 

 vious that land had not been far distant ; and, accordingly, the na- 

 ture of the shells found in it, partakes somewhat of an estuary cha- 

 racter. 



(5.) The banks of sand which lie over the clay, shew that the 

 supply of albuminous sediment which, during the former period, was 

 poured into the ancient sea, at or near this district, had altogether 

 ceased. The fact of these sand-banks running nearly east and west, 

 in all parts of the district, coupled with the discovery in them of 

 stones which must have come from the west, prove the general 

 direction of the current to have been from the west. The sea at 

 this period must have been still at least 300 feet above the present 

 level of it. 



(6.) The next epoch is characterized by a very remarkable 

 change of the relative levels of sea and land. The old bank which 

 runs nearly parallel with the shores of the Firth of Forth, has been 

 formed sometimes out of the fine brick-clay, and sometimes out of 

 the sand last described. The base of this bank on the east shore of 

 Haddingtonshire is about thirty feet above high-water mark ; whilst 

 towards the west it gradually increases to forty feet, which is its 

 height in Linlithgowshire. A bed of shells and sand generally 

 intervenes between said old bank and the present shore. 



(7.) The next period is characterized by a still more remarkable 

 change in the relative levels of sea and land. The upper covering 

 of gravel and boulders has been spread over and above all the de- 

 posits previously described, and it reaches even to the height of 

 900 feet above the sea. This would indicate a sinking of the land 

 or elevation of the waters, to that extent, and a subsequent re- 

 versal of the operation, whereby at length the land again emerged 

 from the waters, and attained the elevation which it now possesses. 

 These boulders are not very much rounded in shape, and do not 

 seem to have been transported from very distant parts. They are 

 frequently angular in shape. 



3. Investigation of a New Series for the Rectification of the 

 Circle. By J. Thomson, LL.D. Glasgow. 



