Correspondence — Mr. Frank Rutley. 93 



GLACIATION OF THE LAKE-DISTRICT. 



SiE, — In your last number Mr. Mackintosli, in his reply to the 

 letters of my colleague, Mr. Wollaston, and myself, states, with 

 reference to my letter in your number for last December, that any 

 want of theoretical agreement between us consists to a great extent 

 in the application of terms. He also says that I have not substan- 

 tiated any charge of inaccuracy of observation in his paper pub- 

 lished in your number for last October. Mr. Mackintosh there 

 stated that in the valley of Kentmere "no traces of moraines, ex- 

 cept perched and scattered blocks, are to be found." 



In my letter I stated my belief that " the old lake, represented by 

 the alluvium of Kentmere, originated partly from damming by a 

 moraine ;" and I also pointed out the occurrence of scratched stones 

 in this valley. The want of theoretical agreement indicated by these 

 two passages does not seem to hinge upon any different " application 

 of terms." 



Mr. Mackintosh calls the mounds which occur in the Kentmere 

 valley " an upland extension of the boulder-drift of the plains." 

 On this I make no comment. Boulders do occur in the valley, to- 

 gether with large numbers of scattered blocks, the latter derived 

 from the immediate vicinity. I still, however, retain my belief that 

 these mounds are the remains of moraines. The position of the 

 mounds, the scratched stones, the alluvial flat, and the gravels at the 

 mouth of the valley, all tend to confirm me in this belief. I do not 

 hold the view about the two great valley-ignoring ice-streams at 

 different periods, with which Mr. Mackintosh credits me. I believe 

 the striae transverse to the axes of the valleys were made when the 

 ice was disappearing from the low ground, and that the ice on the 

 fells, being no longer forced to pass in the direction of valley axes by 

 adjacent valleys full of ice, simply gravitated towards the lower 

 ground, probably obliterating in its passage much previously formed 

 striation, and leaving in its stead these later finishing touches, in the 

 same way that a few strokes of a file wUl obliterate previous file 

 marks made in a contrary direction. 



If Mr. Mackintosh does not believe in the existence of moraine 

 stones on the fells in the neighbourhood of Skeggles Water — What 

 then are the scratched stones which are so numerous there ? They in 

 every respect resemble ordinary moraine stones, and I feel bound to 

 regard them as such until their markings can be satisfactorily ac- 

 counted for by some other hypothesis. In conclusion, I may add that 

 it has not been my intention to look for faults in Mr. Mackintosh's 

 paper, but simply to uphold my observations when the statements of 

 Mr. Mackintosh seemed to contradict or ignore them ; and I trust 

 that his researches among the northern cliffs may lead him to useful 

 and interesting results. 



Frank Eutley. 



H. M. Geological Surtey, 

 January 14, 1871. 



