422 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 22, 



passes by way of the village of Spot and the north side of Doon Hill, 

 throwing down the old red sandstone strata to north. On the east 

 side of Doon Hill another N.N.W. slip cuts off the conglomerate 

 from the newer strata, which it throws down to east. The amount 

 of displacement here must be many hundred feet. Connected in all 

 probabihty with the two last-mentioned faults is the great dislocation, 

 which may be seen on the line of the North British Railway, in a 

 cutting near Broxburn (about two miles from Dunbar). The strata 

 are here seen to be vertical for a considerable distance with a N.N.E. 

 strike. From the sea-shore at Thornton Loch a line of fissure appears 

 to run in a westerly direction by way of Innerwick, Thurston, &c., and 

 across the conglomerate to Barnhead. The aspect of the countiy near 

 this line is remarkably broken and irregular. In the course of the 

 rivulet between Braidwood and Thornton, and in that which runs past 

 Branxton at a point about 400 yards above that place, sections are 

 exposed which show a great dislocation running apparently N.N.E. 

 to S.S.W. At these places the lower carboniferous strata come close 

 up to the conglomerate, and are much crushed and tilted at high 

 angles. At one place they are seen to be retroflexed to a distance of 

 about 100 yards from the slip. 



The above are only some of the chief dislocations which have affected 

 this disturbed district. To investigate the whole would be a work of 

 very great labour and difficulty, though certainly of great interest. 

 In an investigation of this kind, however, the want of exact maps, 

 furnishing an accurate and trustworthy topographical basis for a sur- 

 vey, is felt to be an insuperable barrier. This obstacle will no doubt 

 be removed in due time by the pubHcation of the maps of the Ordnance 

 Survey. 



2. On the Stratified Formations of the Venetian Alps. 

 By Count Achille de Zigno, F.G.S. 



The region to which the present memoir refers contains localities 

 which at all times have attracted the attention of naturalists. The 

 labours of Arduini, Fortis, Da Rio, Marzari, Brougniart, Catullo, Pa- 

 gini, Brocchi, Trettenero, have pointed out its more remarkable fea- 

 tures ; and some of the jNIembers of this Society have cast a rapid 

 glance on the more interesting phseuomena. Feeling comdnced that 

 this portion of our mountains would furnish the clue to the geology 

 of Northern Italy, I have prosecuted my researches for several years, 

 with the object of bringing the stratified formations of the Venetian 

 Alps into co-ordination with the classic deposits of Europe. I have 

 at length succeeded in recognismg and establishing certahi geological 

 horizons, in rectifying some of the earlier observations, and in satis- 

 fying myself of the correctness of others subsequently made. I have 

 had occasion to avail myself of stratigraphical and palaeontological 

 reasoning, according to the localities ; and I indulge the hope that 

 the result of my studies will be a more rational explanation of the 

 structure of our mountains. 



