ABSTRACTS OF LECTURES.
THE EARLY RACES OF
Commencing with Eolithic man as the earliest of English races, the lecturer exhibited a specimen of the unique implements of the plateau race. This race and the subsequent river-drift and cave-men have left no trace in Yorkshire, but Mr. Home was able to add to the interest which surrounds the Neolithic race by exhibiting a photo of a skull of very early type found by him in Wensleydale, and by his descriptions of his other discoveries in the same neighbourhood, including Bronze Age weapons from the Lady Algetha Cave and Roman Pottery and other later objects adding to the knowledge of Bronze age men ("Ancient Britons") and the Romano-British people of this country.
THE PAST HISTORY OF THE
The modern theory of the origin of River Systems is--given a large area of land having a general slope to the sea, a river system will be formed in the general direction of the slope. These rivers are known as "Primary," their course is fairly direct and they receive tributaries from the more elevated regions between them. These tributaries are known as “Secondaries”. The general result of the denudation of this area is to form longitudinal valleys connecting the primary streams and more or less at right angles to the latter. If any one of two primary streams flows at a lower level than the other the waters of the latter will generally be captured by the former on the lines of the longitudinal valleys. Applying this to the case of the Trent, we see that, assuming the land to the West of the Chalk and Oolitic beds to have been much higher formerly than at present and that the Humber and Trent were primary streams (the former reaching the sea as at present, and the latter by way of Lincoln Gap to the Wash) both having tributaries draining, amongst other districts, the area between Newark and Alkbro, the Trent was captured by the Humber along the longitudinal valley formed through a group of tributaries of the Humber having denuded the intermediate Keuper strata. The lecturer referred to the historic references to the Fenland and Trent floods, and he shewed that so far as History goes it confirmed his theory.
SOME ALPINE GLACIERS. BY, PERCY F. KENDALL ESQ.,
F.G.S:, Vice-President of the Society and Professor of Geology,
Mr. Kendall stated that his lecture was mainly based on the results of observations of glaciers, moraines, etc., made during his last visit to the Alps, July-August,1895. Commencing with a series of views of the Jura, he pointed out the, morainic mounds with an occasional erratic block to which we owe the present advanced state of Glaciology. Passing on to the Zermatt district, he had placed upon the screen an excellent set of photographs he had taken, of the Gorner, Grenz, Schwarze, Theodule, Furgg and Zmutt Glaciers, shewing excellent examples of lateral and medial rock trains, one of the latter rising in the middle of the glacier without any visible means of supply. The lecturer pointed out the curious effect of a dry lake in the ice becoming a hill, through having its bed covered with gravel and thus afforded some protection from the rays of the sun while the surrounding ice is undergoing ablation. He also dealt with the crevasses shewing how the morainic matter was engulfed and disgorged by them and how it formed gravelly beds interstratified with the glacier itself. A unique photograph of a glacier at work upon the live rock which he had taken at considerable risk, shewing the churning up of mud, fragments of rock, etc, a lecture on glaciation in itself, the floating icebergs of the Marjelen See and the enormous moraines of Ivrea were also shewn and explained.
Copyright Hull Geological Society 2016