Geological Society of London. 429 



the ridges of tbe high land at the head of the valley. At the 

 same time the author proves that it must have passed over to the 

 lower levels, and that it undoubtedly deepened many of the valleys 

 which happened to lie in its course. He considers that the Scotch 

 ice could not v/ell have exceeded 2400 or 2500 feet in thickness; and 

 finally arrives at these conclusions: — that angular moraine-like drift 

 of the high ground, the upper and lower tills, the deposits which 

 form the eskers, and the numerous stranded boulders, are the result 

 of the melting of a vast thickness of land-ice, charged throughout 

 with stones and boulders of nearly every kind of rock occurring 

 within the area in which the body of the ice originated. 



19. "Geological Observations made on a Visit to the Chaderkul, 

 Thian Shan range." By Dr. F. Stoliczka, F.G.S. 



In this paper the author gives an account of the geology of the 

 district traversed by him in his journey from near Kashgar to lake 

 Chaderkul on the Eussian frontier, a distance of about 112 miles, 

 his route lying among the southern branches of the Thian Shan 

 range. 



Three principal ridges were crossed. The first, or " Artush ridge," 

 consisted of newer Tertiary deposits of bedded clay and sand, mostly 

 of a yellowif-h-white colour. These "Artush beds" were traced by 

 the author for a distance of 22 miles. The southern slopes of this 

 range were covered with gravel from 10 to 15 feet thick, which 

 passes into a conglomerate with a thickness of about 200 feet. 



The second, or " Kokan range," is formed on the southern side of 

 old sedimentary rocks, whilst the northern is occupied by newer 

 Tertiary deposits and basaltic rocks, the former consisting of shales 

 and limestones, in which the author found some fossils, inducing 

 him to refer them to the Trias. These are succeeded by some dark- 

 coloured shales, slates, and sandstones, dipping at a high angle to 

 the north. 



On the denuded edges of these the newer Tertiaries rest, consist- 

 ing of sandstones interstratified with basaltic rocks. These latter 

 increase in thickness till just beyond Kuija an old " somma " is 

 reached, with perpendicular walls rising to a height of 1500 feet 

 above the river. The cone of the volcano has disappeared by sub- 

 sidence. 



The third ridge, " Terek-tagh," consists of old sedimentary rocks, 

 chiefiy limestones. 



20. " Note upon a recent Discovery of Tin-ore in Tasmania." By 

 Charles Gould, Esq., B.A., F.G.S. 



In this paper the author states that the ore has been found in 

 large masses in situ, and that the containing rock is lithologically 

 distinct from the ordinary ternary granite which forms the whole 

 of the stanniferous country of Queensland. The discovery waS 

 made at Mount Bischoff, in the N.W. portion of Tasmania, but as 

 the district is covered by scrub an exact estimate of the exposed 

 area of stanniferous rock is as yet impossible. It does not appear to 



