112 Rev. J. Clifton Ward — Geology of the Lake District. 



principally to marine action. Boulders carried far from the parent- 

 rock by glacier-ice at one time, and floating-ice at another. Glacial 

 scratches partly produced by a confluent glacier-sheet, partly by 

 small separate glaciers ; also occasionally made by floating-ice during 

 the period of submergence. Moraines left by an early set of glaciers, 

 much modified by subsequent aqueous action ; and more perfect 

 moraines left by the most recent local glaciers. Many years study 

 of these phenomena has led me to draw the following general 

 conclusions, which I take in part from my Survey Memoir, p. 97 : 



" At the commencement of the cold period small glaciers occupied 

 the heads of the various valleys, and, as the cold continued and 

 increased, they became larger and larger, until, in many cases, they 

 united, overlapping the lower ridges parting valley from valley, and 

 forming one great confluent ice-sheet, the movement of which was 

 determined to the north and to the south, or east and west — as the 

 case might be, in different parts of the district — by the main water- 

 parting lines. A great quantity of rocky debris was moved onwards 

 and left scattered over the countiy, partly by the first formed 

 moraines being pushed forward, and partly by the ice overriding the 

 same and dragging on and triturating the fragments beneath it. In 

 this way the Till was formed, sometimes left in rock-sheltered 

 upland hollows, but most largely deposited on the lower and less 

 inclined ground. 



"Whether this first land-glaciation was interrupted by one or 

 more mild periods, the deposits in this district do not prove. 

 As the final close of this epoch of intense glaciation drew on, 

 moraines were left by the retreating glaciers plentifully scattered in 

 every valley, but the glacial streams and rivers must have made 

 much havoc amongst them, cutting them up and bearing away their 

 material to lower levels. 



"Then, when the cold had disappeared, began a submergence of the 

 district to a very considerable extent. As the land sank, the old 

 moraine material was sifted, sorted, and partly rounded. At the 

 ends of some of the fiords or straits, sand-bars were formed ; but, 

 as there was no floating-ice during the earlier stages of submergence, 

 these sand and gravel deposits enclosed no large boulders. The 

 district became gradually converted into an archipelago, and currents 

 circulated among the islands. When depression had gone on to the 

 amount of 1,000 feet or less, the cold returned and ice-rafts bore 

 blocks from one part to another. 1 In many cases the direction in 

 which currents swept the floating-ice was the same as that of the 

 old glaciers, and thus boulders were transported along the same 

 course at different periods and by different means. Sometimes, 

 however, or at certain parts, marine currents bore floating ice, with 

 its boulders, in directions opposed to, or much at variance with, the 

 old glacier courses. Thus, when the land stood about 1,200 feet 

 lower than at present, a current, sweeping the north-western out- 



1 For maps showing probable form of land at different stages of submergence, see 

 papers by the author on "Lake District Glaciation," Qtmrt. Journ. Geol. Soc, vol. 

 xxix. p. 422, and vol. xxxi. p. 152. 



