373 
G. M. Daicson — Geologij of British Columbia. 
Silurian age, aud tliey iudicate certain theoretical conclusions which 
follow from this determination. 
9. “ On the Superficial Geology of British Columbia.” By George 
Mercer Dawson, Esq., F.G.S., Assoc, R.S.M., of the Geological 
Survey of Canada. 
The author stated that the rock-striation and fluting on the south - 
eastern peninsula of Vancouver’s Island shows that at one time a 
great glacier swept over it from N. to S., filling the Strait of Georgia, 
50 miles broad in places, and having near Victoria a thickness of ice 
of over 600 feet. Traces of this glacier also occur on San Juan 
Island, and on the coast of the mainland. The deposits immediately 
overlying the glaciated rocks, besides what may be moraine profonde , 
locally developed, are sandy clays and sands, arranged in water, and 
sometimes containing marine Shells. The lower beds, at least, of 
these, were probably formed at the foot of the retreating glacier, the 
sea Standing considerably higher than at present. The northern part 
of the Strait of Georgia and the fjords opening into it, and the fjords 
north of the Strait, show ice-action to a height of above 3000 feet. 
Terraces on the coast of the mainland are rare, and never at great 
elevations. 
The interior plateau of British Columbia shows a System of 
glaciation from N. to S., traces of which have been observed above 
3000 feet. Subsequent glaciation radiating from the mountains 
also occurs. The superficial deposits here are either unmodified or 
modified. The former, representing the Böulder-clay, occurs at 
nearly all heights up to over 5000 feet; the latter characterizes 
nearly all localities below 3000 feet, and is most extensively 
developed in the northern low country, where it forms a white 
silt. or loess. The interior is marked with shore-lines and terraces 
up to 5270 feet. Moraines occur in great nümbers, most of them 
marking stages in the retreat of glaciers towards the mountains, 
although some may have been formed in connexion with the N. and 
S. glaciation. 
The sequence of events in the interior, according to the author, 
seems to have been as follows : — Glaciation from N. to S., with 
deposit of Boulder-clay ; formation of terraces by lowering of water 
surfaces, accompanied or followed by a warm period ; advance of 
glaciers from the mountains, and formation of lower terraces ; and 
retreat of glaciers to their present limits. The glaciation of Van- 
couver’s Island may have occurred during both cold periods or durin g 
the second only. 
The author considers the assumption of the production of the 
N. to S. glaciation by an ice-cap to be attended with great difficulties, 
and seems to favour the notion of its being effected by the accumu- 
lation of ice on the country itself, and especially on the mountains 
to the N., filling the central plateau in going southward, and passing 
seaward through the gaps and fjords of the coast ränge. 
10. “The Exploration of the Ossiferons Deposit at Windy Knoll, 
Castleton, Derbyshire, by Rooke Pennington, Esq., LL.B., F.G.S., 
and Prof. W. Boyd Dawkins.” By Prof. W. Boyd Dawkins, M.A., 
F.R.S., F.G.S. 
