H. B. Woodward — Inversion of Carboniferous Strata. 455 



however equable, to find that rocks so old as the Cambrian, sub- 

 jected to vicissitudes which might multiply these effects a thousand- 

 fold, present lengthened sections of almost rectilinear uniformity. 

 Viewing the a priori features of the question from a stratigraphical 

 point of view, Mr. Judd asks,^ " What reason can be adduced for 

 doubting that those great disturbing forces — which, during and sub- 

 sequently to the Oligocene and Miocene periods, have given rise to 

 such startling results in the contortion and even in the inversion of 

 the rocks of the Alps, but which at the same time have produced 

 only inconsiderable effects in the areas immediately surrounding 

 them — must have originated, in different parts of the great lines of 

 drainage descending from those mountains, such inequalities of 

 movement as could not fail to result in the formation of lake- 

 basins?" Fully recognizing these probabilities in the case of the 

 Alps, I can yet appeal to my friend Mr. Judd to reverse the argument, 

 and admit the much greater improhahilities in the area I refer to. 



In concluding, it would well beseem me to apologize to older and 

 tried geologists for venturing to differ from them. I hope, neverthe- 

 less, that anything, however little, that tends to the elucidation of a 

 difficult question, will be received in the spirit in which it is offered. 

 I had looked, I confess, to Mr. Bonney to assume the intermediate 

 position which his views on the lakes of the Engadine and a recent 

 statement in the Geological Society ^ rendered probable as his present 

 one, but his letter fails to justify this hope. 



It only remains to add, that the assumption made at the beginning 

 of this communication — namely, that lakelets were at least occasion- 

 ally scooped by glacier-ice — I hope soon to place beyond question. 



Y. — Additional Kemakks upon Inversions of Carboniferous 



Strata in Somersetshire. 



By Horace B. Woodward, F.G.S., 



Of the Geological Survey of England and Wales. 



IN the Geological Magazine for April, 1871, I attempted to 

 account for the mode of occurrence of the masses of Carbon- 

 iferous Limestone that are found in the midst of the Coal-measure 

 country at Luckington and Vobster in Somersetshire, and I then 

 drew a picture of a faulted and inverted anticlinal to explain the 

 phenomena. Mr. McMurtrie, who has more recently re-opened the 

 discussion on the subject, and in a friendly manner assailed my 

 theory, again asserts that the Limestone masses '* must in some 

 way have been folded over " from the Mendip range. He has very 

 clearly brought forward all the local facts that bear upon the 

 question, and has represented in diagram the mode by which he 

 would account for the position of these isolated areas of Carbon- 

 iferous Limestone.^ No one is so familiar as is Mr. McMurtrie with 

 the detailed structure of the Somersetshire Coal-field, and I look 



1 Geol. Mag. for January, p. 11. 



2 See discussion on Mr. Clifton Ward's paper already referred to. 



3 Proc. Bath Nat. Hist, and Antiq. Field Club, 1876, vol. iii. p. 287. 



