692 BEFOitT — 1887. 



the Aare glacier, the Reuss gkcier, or the Rhine glacier ; and the prevalent idea 

 of a ' first glacial epoch ' in which the glaciers had no ternnnal moraines was also 

 unsupported by the author's observations. 



The great ice-sheet which once covered northern England was found to be com- 

 posed of a number of glaciers, each of v^'hich was bounded by its own lateral and 

 terminal moraines. The=e glaciers were studied in detail, beginning with the east 

 of England, and tlie North Sea glacier, the AVensleydale glacier, the Stainmoor 

 glacier, the Aire glacier, the Irish Sea glacier, and the separate \Velsh glaciers- 

 were each found to be distinguished by characteristic boulders and to be defined 

 by well-marked moraines. The terminal moraine of the North Sea glacier, filled 

 with Norwegian boulders, may be seen in Holderness, extending from the mouth 

 of the Ilumber to Flamborough Head ; it consists of a series of conical hills 

 enclosing meres, The moraine of the Stainmoor glacier, cliaracterised by blocks 

 of Shap granite, may be followed northward along the coast past Scarborough and 

 Whitby ; then west along the Cleveland Hills ; then south again through Oulstou 

 to the city of York; then west to near Allerton, wliere the Staiinnoor glacier is 

 joined by the Wensleydale glacier — a fine medial moraine marking the line of 

 junction. The Wensleydale glacier is characterised by boulders of carboniferous 

 limestone and sandstone, and its lateral moraine is followed imrthward through 

 Wormald Green, Markington, Fountains Abbey, and along the Permian outcrop to 

 Masham, where it turns west to Wensleydale, passing Jervaulx Abbey, and running 

 up the valley. North of Wensleydale the moraine of the Stainmoor glacier is 

 followed through Richmond to Kirkby Ravensworth and weitward to the moun- 

 tains, where the glacier attained an elevation of 2,000 feet. Thus the Stainmoor 

 glacier, a tongue of the great Irish Sea glacier, had been divided into two branches 

 by the Cleveland Hills, one branch going south to the city of York, which is built 

 on its terminal moraine, the other branch flowing out of the Tees and being de- 

 flected southwards along the coast by tlie North Sea glacier, with which it became 

 confluent. 



The Irish Sea glacier, the most important glacier of England, came down from 

 Scotland, and, being reinforced by local ice-streams, and flowing southward until 

 it abutted against tlie mountains of Wales, it was divided into two tongues, one 

 of which flowed to Wellington and Shrewsbury, while tlie other went south-west 

 across Anglesey into the Irish Sea. This great prlacier and its branches are all 

 outlined by terminal moraines, described in detail. A small tongue from it, the 

 Aire glacier, was forced eastward at Skiptnn and has its own distinctive moraine. 

 In the neighbourhood of Manchester the great moraine of this Irish Sea glacier 

 may be followed through Bacup, Hey, Staleybridge, Stockport and Macclesfield, 

 beinir as finely developed as the moraines of Switzerland and America. South of 

 Manchester it contains flints and sliell-fragments. brought by the glacier from the 

 sea-bottoiu over wliich it parsed. At Manchester the ice was at least 1,400 feet 

 thick, being as thick as the Rhone glacier. 



The great terminal moraine now described of the united glaciers of England is 

 a very sinuous line, 550 miles in length, extending from the mouth of the Humber 

 to the fartliest extremity of Carnarvonshire, and, except where it separates the 

 Welsh glaciers from tlie North Sea glacier, everywhere marks the extreme limit of 

 glaciation in Endand, and is an important feature which might well hereafter be 

 marked on the geological map of England. 



4. On some important E.vtrn-Morainic Lakes in Central England, North 

 America, and elsewhere, during the Period of Maximum Oladation, and 

 on the Origin nf Extra-Morainic Boulder-clay. By Professor H . Carvill 

 Lewis. 



The lakes so characteristic of all glaciated regions are due to several causes. 

 Some few are due to an actual glacial scooping out of the rock floor, mjiny to an 

 irregular deposition of the drift, bj' which former watercourses are obstructed, and 

 still others to the ti-rminal moraine or to the glacier itself. These latter, known as 

 inorainic /f/u v, may be divided into intei'-morainic lakes, moraine meres, and extra- 



