28 A. MacEwcn Peach — Glacial Didribiition of 



Tracing the northern limit of the track as it passes eastward, we 

 find that it ascends the higher ground which rises across its path. 

 North of Milton the boulders of the northern limit have reached 

 an elevation of 1,000 feet, while on Brown Hill they are more than 

 1,250 feet above sea-level. From Brown Hill the northern limit 

 has a tendency to turn northwards, and from that point to Lairds 

 Hill, due north of Kilsyth, the carry is E.X.E., the altitude at 

 places being more than 1,300 feet. From this last point the carry 

 is almost due east, the direction of ice-flow being unaffected by 

 surface features. The northern limit is fairly well marked, and on 

 the lower ground, north of Townhead Reservoir (see Map 1), its 

 altitude is not more than 800 feet. To the east the boulders become 

 scarcer, and the limit is not so well defined ; it passes south of Denny 

 and Larbert, and to the east of the latter place the trail is concealed, 

 the drift being covered by the deposits of the various raised beaches 

 of the Forth area. 



The southern limit of the boulder track is also well marked. East 

 from Lennoxtown the boulders do not come below the 300 foot 

 contour-line till they reach a point east of Milton. Here also no 

 influence on the direction of ice-flow can be attributed to the local 

 surface features. For a short distance there is a slight southward 

 deviation, but the eastern trend is resumed in the neighbourhood 

 of Antermony Dam, between Milton and Kilsyth, and the direction 

 even tends slightly to the north, running almost E.K.E. till at 

 Camelon the boulder-clay is overlain by the Hundred Foot beach 

 deposits already referred to. The boulder track up to this point, 

 some 15 miles from its origin, is never more than 2A- miles aci'oss. 

 It is well defined, and the number of erratics is very large in 

 consideration of the size of the parent mass. Farther eastwards the 

 raised beach deposits and the gravels of the Kaimes for a time 

 obscure the boulder-clay, till, east of Polmont and north of Linlithgow, 

 boulders are again found, the northei-n limit of the ti'ack entering 

 the Forth just to the east of Bo'ness. 



The coast all along the shores of the Forth is very suitable for 

 the detection of the boulders, as it is covered just about high-water 

 mark with stones derived from the destruction of a large" amount 

 of boulder- clay. Along the shore from Bo'ness to beyond South 

 Queensferry these essexite boulders occur till the southern limit of 

 the track is. reached between Hound Point and Cramond. From 

 Cramond to Portobello no essexite erratics were found, although this 

 shore is a very favourable one for their observation, the boulders 

 on the shore representing the result of the destruction of a very large 

 amount of boulder-clay. It has not been considered necessary to 

 look for boulders on the shores immediately east of Portobello,' but 

 careful research on the promontory of North Berwick has failed to 

 reveal any erratics from the Lennoxtown essexite, a result which 

 might have been predicted from the trend of the glacial stride. Thus 

 the southern limit of the track evidently lies within the area now 

 covered by the Firth of Forth. This conclusion has been drawn 

 from a consideration of observations on the ice-mouldings and strise 

 between Edinburgh and North Berwick, which show that the direction 



