Transacttom. 83 



mediately we reach equally interesting sections of the 

 Silurian, east and west of the Goldielea viaduct. Passing 

 by many minor but not unimportant features we reach at 

 the Dalbeattie cutting the Syenite, usually termed Granite. 

 Immediately on crossing the River Urr we come again upon 

 a succession of sections of the Silurian, which accompany us 

 more or less to Castle-Douglas. Thence to Bridge of Dee 

 Station, where we left the train, and the Bridge of Dee itself, 

 were pointed out unmistakable indications of glacial action 

 on the exposed rocky surface. The ujDturned edges of the 

 Silurian strata were again well seen in the bed of the stream 

 on crossing it to Threave Castle. After visiting Kelton Hill 

 we proceeded along the Kirkcudbright road for a few miles 

 to visit the site of a lead mine. This, so far as we could 

 exainine it, consisted of a horizontal shaft at the bottom of a 

 cliff at the side of a burn. The traces of lead and zinc 

 found were somewhat vague and uncertain, although the 

 rock liad the usual appearance of veinstone. The cliff con- 

 sisted of our old friend the Silurian, and what was perhaps 

 more interesting to us, it exhibited a fine though small ex- 

 ample of contorted strata. In the immediate neighbourhood 

 a large mass of Felstone Porphery stood out prominently, a 

 not unfrequent associate of the Silurian in the South of 

 Scotland. The surface of the fields and grounds around is 

 characterised by its broken irregular features. These are 

 due to a succession of roiuided, rocky knolls, the so-called 

 Roches Moutonees, and are as fine an example of this variety 

 of glacial action as can be seen anywhere. Lower down in 

 the glen w'e came upon a section produced by the burn which 

 runs through it, which presented us with a fine specimen of 

 glacial till. Thus we had, in this narrow spot, a very crowd 

 of interesting objects for observation, thought, and study. 



The fouith excursion was to Lochmaben, across the ridge 

 of the Lochmaben and Mouswald hills, intervening between 

 the valleys of the Nith and Annan. Starting by the Glasgow 

 and South- Western Railway for the Racks Station, the mem- 

 bers once more pass through a series of gravel mounds, as at 

 Gasstown, Dargavel, Racks, &c. ; second, through a portion 

 of the Solway moss, an ancient arm of the sea. Almost 

 immediately after leaving the station they commence the 

 ascent of the Lochmaben hills, which the members are now 

 aware consist of the Silurian system, the strike running 

 nearly east and west, and dipping to the north and east at a 

 very high angle. The character of the rock is occasiomdly 

 seen in quaniea, cliffs, and uxposed rock surfaces along the 



