Correspondence — Rev. T. G. Bonney. 93 



south-east. Three hundred feet would not only cover the major part 

 of the Weald with the sea, but would also convert the south-east of 

 England into an archipelago, in which the extent of the land-area 

 would be intermediate between that shown in my restoration-map 

 No. I., and that shown in No. II. ; and it is to the period intermediate 

 between these two restorations that I have assigned the upthrow of 

 Portsdown Hill and the Hogsback. 



The President connects the bed in question with the Brighton 

 raised-beach ; and if that connexion be well founded, we have this 

 preponderance of the westerly upcast shown to the extent of nearly 

 300 feet in 40 miles, the Brighton beach being but little above the 

 sea-level. 



Searles V. Wood, jun. 



CIRQUES AND TALUSES. 



SiK, — The paper on Cirques and Taluses in your last number (p. 10), 

 wherein my friend Mr. Fisher notices my theory of the formation of 

 Cirques, seems to call for a few remarks on my part. I feel much 

 indebted to him for the kind manner in which he has expressed his 

 divergence of opinion from myself, and regret that, notwithstanding 

 his able plea for glaciers, I must hold to my words. 



He concludes that " a cirque, though not excavated by a glacier, 

 is strictly a glacial phenomenon," while I have stated that, " the 

 completeness of the cirque as a whole forbids us — unless we assign it 

 entirely to glacial action — to suppose that it was more than slightly 

 altered by this." To some extent the difference between us is more 

 a question of words than anything else. I hold that atmospheric and 

 stream action made the cirques ; Mr. Fisher thinks that, by whatever 

 agent they were made (probably as I have suggested) , a glacier cleaned 

 out the rubbish which must have accumulated in them prior to the 

 Glacial epoch, and that, instead of saying "in not a few corries and 

 cirques the transporting power (of stream) can hardly keep pace with 

 the excavatory," I should have said can not keep pace. With regard to 

 the former point, the glacier would most probably clear out the cirques, 

 but I do not know that there is any evidence to show that they were 

 formerly more choked up than they now are. As to the latter, I used 

 the " word of doubtful signification " deliberately ; because, although 

 I think that not seldom the debris is on the whole accumulating, the 

 increase is so slight as to be almost imperceptible ; so that any 

 unusually heavy storm may in an hour wash away the accumulation 

 of a century. Debris strewn over iceworn slopes below the cliffs 

 and screes masking the junction between these two (as in the case 

 referred to) do not necessarily prove that the cirque is filling up ; 

 they only mark a stage in the quarry work of nature. The sawing 

 of streamlets, aided by frost, etc., brings down the stone from the 

 face of the cliif in fragments of various sizes ; these, often broken 

 smaller by their fall, lie on the slopes below, subjected to the same 

 action of rain, heat, frost, until they are reduced to yet smaller frag- 

 ments or even to fine dust, or are swept away by some swelling of 



