362 Dr. Walter Flight— History of Meteorites. 



surface of the lower lying Dale rocks must be at least equal, area for 

 area, to what was removed from Wastdale Crag. Hence we are led 

 to the conclusion that the ice-sheet effected some very important 

 modifications of form in the old preglacial valleys. Where the ice 

 remained for long periods, there can hardly he any doubt that many 

 of the valleys were both deepened and widened, in some instances to 

 a considerable extent ; and also that the peculiar mode of action of the 

 ice tended everywhere to modify the pre-existing form of the surface 

 and even to replace part of this by sculpturing that is very different 

 from anything that, under existing physical conditions, could possibly 

 be produced by any kind of Subaerial Erosion. 



The origin of these terraces and scars of limestone has, perhaps, 

 been dwelt upon here at greater length than its inij)ortance might at 

 first seem to require, because the existence of such features in a rock 

 so easily affected by atmospheric agencies as limestone is affords us 

 a clear proof that whatever left them in so high relief beyond the 

 associated less-easily weathered beds was an agent that acted with 

 greatest effect upon those rocks that could least withstand mechanical 

 erosion and disregarded their varying power of resistance to erosion 

 by Subaerial means. 



We know that the valleys where these features occur were at one 

 time filled to the highest points with ice ; we also know by the 

 position of certain marks of glacial origin that but little atmospheric 

 erosion has been effected at those points in Post-glacial times ; hence 

 the conclusion seems inevitable that all the rock features whose 

 origin cannot be referred to any form of Subaerial erosion, but which 

 are clearly due to erosion by some mechanical means, have been the 

 work of the ice. Not only the terraces of limestone, but the asso- 

 ciated terraces and scars of sandstone and grit, must have originated 

 in the same way. Hence one is led to regard nearly all the more 

 prominent rock features of these well-glaciated parts as in one way 

 or another the result of Glacial Erosion. 



V. — A Chapter in the Histoey of Meteorites. 

 By Walter Flight, D.Sc, F.G.S., 



Of the Department of Mineralogy, British Museum. 

 {Continued from page 320.) 



1790, July 24th. — Barbotan and Roquefort, Landes, France. 1 



A correspondent communicated to Nature a reference to a descrip- 

 tion of this celebrated fall of meteorites, which is to be found in 

 Gruithuisen's NaturgescMchte des gestirnten Himmels 407. As it does 

 not appear to have been known to Buchner, it may be placed on 

 record here. 



1803, April 26th.— L'Aigle, Orne, France. 2 



While at the end of the last century reports from time to time 

 obtained circulation, to the effect that stones had been seen to fall 

 from the sky, and while these reports were generally discredited as 



1 Nature. February 1st, 1872. 



2 E. H. von Baumhauer. Archives Neerlandaises, 1872, vii. 154. 



