578 Geo logica I Society : — 



pole southward over both continents at the same time, causing 

 cyclonic conditions in the Atlantic both in summer and winter. 

 Such a condition of things would have flooded Western Europe with 

 warm southerly winds. No such meteorological difficulties arise if 

 the hypothesis that the more important glacial and interglacial 

 periods alternated in the western and eastern continents be adopted. 

 Thus persistent and excessive cold in North America during the 

 winter of 1898-99 was coincident with abnormal warmth in Europe; 

 the winds were northerly and polar in America, southerly and 

 strictly complementary in Europe. 



On the other hand, the effect of an ice-sheet anticyclone extending 

 from Greenland to Central Europe might have been to force the 

 storm-tracks of the North Atlantic to the south-west, producing 

 warm south-easterly winds in Labrador, which would have tended, 

 moreover, to divert the surface-currents of the North Atlantic from 

 the European to the American coast. The glaciation of Great 

 Britain could only have happened at a time when the Icelando- 

 British Channel was closed. No permanent ice-sheet could have 

 existed in Britain and Scandinavia while the influence of the Gulf- 

 stream was as it is at present. 



It is possible that the shifting of glacial conditions from one 

 side of the Atlantic to the other may have been due to differential 

 earth-movements. 



The views taken in this paper afford a simpler explanation of 

 geological facts than those usually adopted. Instead of supposing 

 that the climatic changes of the Great Ice Age, several times 

 recurrent at intervals of a few thousand years, were due to 

 astronomical or physical causes, it is suggested that the climate of 

 the northern hemisphere being, from some unexplained cause, colder 

 than that of our era, conditions of comparative warmth or cold may 

 have been more or less local, affecting the great continental areas 

 at different periods. 



May 22nd.— J. J. H. Teall, Esq., M.A., Y.P.E.S., President, 

 in the Chair. 



The following communications were read : — 



1. ' On the Skull of a Chiru-like Antelope from the Ossiferous 

 Deposits of Hundes (Tibet).' By Bichard Lydekker, Esq. 



2. ' On the Occurrence of Silurian (?) Rocks in Eorfarshire and 

 Kincardineshire along the Eastern Border of the Highlands.' By 

 George Barrow, Esq., F.G.S. 



These rocks occur in three lenticular strips between the schistose 

 rocks of the Highlands and the boundary-fault next the Old Bed 

 Sandstone. The largest is about 20 miles long, and extends almost 

 from Cortachy to beyond the Clattering Bridge ; it is about f mile 

 wide at its widest. The rocks are divided into two groups : the Jasper 

 and Green-Rock Series below and the younger Margie Series above. 

 A section along the North-Esk River is described in detail, and other 

 sections referred to it. The lower division consists of fine-grained 

 sandstones (bearing microcline), grey slaty shales, jaspers (some- 

 times containing circular bodies resembling radiolaria), and a variable 



