4 PROFESSOR P. F. KENDALL AND MR E. B. BAILEY 



to the Silurian Uplands. Once upon the top of the watershed the current turned for a 

 while into a direction markedly south of east ; and the same deflection is noticed where 

 the congestion in the basin of the North Sea began to make itself felt upon the great 

 ice stream issuing from the Firth of Forth ; for the latter had to pass out in both 

 directions, and thus the current crossing the eastern Lammermuirs bent round into 

 approximate parallelism with the coast towards St Abb's Head. The record of the march 

 of the ice sheet is chiefly preserved in the boulder clay, which it deposited as it went. 

 Our own observations in this connection relate for the most part to the northern front of 

 the Lammermuir Hills and to the district intervening between them and the Firth of 

 Forth. They have enabled us in the first place to confirm Prof. Geikie's * record of 

 Highland erratics, since the latter occur throughout the whole area and may be 

 recognised in good numbers even as far to the south-west as Tynehead. Boulders of 

 carboniferous rocks have been carried in company with those from the Highlands far 

 out on the Silurian Uplands, and, according to Dr Peach, over the other side into the 

 Merse of Berwickshire ; while to the north, along the Old Red and Calciferous Sandstone 

 tracts lying at the foot of the hills, the whole country is swathed in boulder clay 

 abounding with limestone, coal, and andesite fragments, all indicating a carry from the 

 west in a direction oblique to the course of the Lammermuirs. East of the outcrop of 

 the Garleton volcanic zone the same tale is told by the appearance of trachytes and 

 basalts among the boulders of the drift ; for instance, fragments of the former have been 

 found in boulder clay as far to the south-west as White Castle, where the road leads 

 across the hills from Garvald. Only two more instances need be cited, and these are of 

 special importance, as they serve to indicate in an unusually emphatic manner the 

 direction of the ice flow for the districts which they represent. At Port Seton and 

 along the coast to the east certain conspicuous boulders of conglomerate occur which 

 resemble the Craigmillar conglomerates of the Edinburgh district, and Mr Clough has 

 met with a train of similar erratics alone the coast for a mile east of Dunbar. This 

 would indicate an average direction of transport of E. 5° N. across the intervening 

 district. The second example illustrates the deflection of the course of the ice sheet 

 when once it had crossed the watershed. Dr Peach has traced the carry of the granite 

 boulder derived from the Priestlaw mass, and found that they indicate an ice flow in a 

 south-easterly direction towards Longformacus. 



The evidence just considered may usefully be supplemented by reference to the 

 erosion effects produced by the great ice sheet. Strise have been but poorly preserved, 

 and all records come from the low-lying districts.t They may be tabulated as follows, 

 from west to east ; — 



Kippie Law (half a mile N. of Traprain Law), E. 



Traprain Law (steep south-western face), E. 10° S. 



* Great Ice Age, 1894, p. 195. 



t Striae in the Garleton Hill area are abundantly preserved, and are well known. Their direction is entirely in 

 accord with that indicated in the sketch map. 



