SIR HENRY" H. HOWORTH, D.C.L.;, F.R.S., OX ICE OR WATER. 223 



Section ill the Banks of the Rihhlc near Balderstonc Hall. 



Approximate 

 thickness. 



3. Upper Boulder Clay : Eed, partially stratified 



clay with some stones round or sub-angular 60 feet. 



2. Interglacial Beds : Stratified beds of water- 

 worn gravel and sand ... ... ... 50 „ 



1. Lower Boulder Clay (Till). Dark, stiff clay 



with angular blocks and pebbles ... ... 10 „ 



Total 120 feet. 



The sandstone supporting these deposits was not visible at 

 the water edge, but was doubtless close underneath.* 



These deposits are spread over a large area uf the north and 

 centre of England, and are representative of the three divisions 

 of the glacial period — the lowest of the land ice-sheet — and 

 period of maximum cold and elevation; the middle, of the 

 Interolacial subnierg;ence and the return of warmer conditions 

 due to the greater intiuence of the Gulf Stream ; and the 

 Upper, of partial re-elevation and deposition under the waters 

 of a glacial sea, charged with mud derived from the still 

 existing glaciers which retained their hold on the higher levels 

 of Wales, Cumberland and the Scottish highlands. The occur- 

 rence of this stratified upper boulder clay with shells explains 

 one of the difhculties which have beset our author, as also 

 j\lr. Warren Upham. The shells do not (as far as I. am aware) 

 occur in the Till or Lower Boulder Clay, but only in the Upper 

 Boulder Clay which was deposited in sea-water.f 



Our author, when dealing with tlie fiords, denies that they 

 are partially submerged ri\'er-valleys. When writing on the 

 subject of the Norwegian fiords for this Institute, I assumeti as 

 heyond controversy that such was the casej ; l3ut our author 

 raises the objection that they are deeper some distance up from 

 their mouths than at the outlets themselves. This remarkable 

 fact, the knowledge of which is derived from the soundings on 

 the Admiralty charts, I had asceitamed for myself, but it did 

 not lessen my belief in tiie fiuviatile origin of tiiese remarkable 



* "Geology of tlie Burnlev coal field, etc.," 3Iem. Geol. Survey, p. 129, 

 Pig. 2« (1875). 



t There may be conceivable cases where si i ells may be met with in the 

 Till, but these are quite exceptional. The Till, when resting on solid rock, 

 has its tioor generally striated and polished. 



X "On the Physical History of the Norwegian Fjords," Trans., 

 vol. xxxiv, p. 125. 



