Published online by Cambridge University Press: 01 May 2009
This pit has already formed the subject of communications to the Society. In one read February 16th, 1863, and in a subsequent paper published in the GeologicalMagazine, Vol. II., p. 529, Mr. Seeley maintained, as I believe Professor Sedgwick had always held, that the singular juxtaposition of Kimmeridge Clay, Cretaceous rocks, and Boulder-clay, was due to faulting. In 1868 the Rev. O. Fisher communicated a paper, in which he accounted for the phenomena, by considering the Cretaceous beds as a huge boulderlike fragment, dropped into a valley which it had excavated in the Kimmeridge Clay, with the intervening space filled up with Boulderclay. Shortly after this had been read, Mr. Seeley published a paper in the GeologicalMagazine (Vol. V., p. 347), in which he attacked Mr. Fisher's view. The explanation of the phenomena may therefore be fairly regarded as still sub judice. During the last three years I have from time to time visited the pit, and purpose to lay before the Society the conclusions at which I have arrived, from repeated comparison of the rival theories with the sections exhibited during the progress of the works.
page 403 note 1 Mr. Fisher's paper was printed subsequently, Vol. V. p. 407.
page 405 note 1 If further proof were needed, I found on one occasion a mass of chalky Boulder-clay, some two feet in diameter, included in the Kimmeridge Clay, just above the floor of the pit.
page 406 note 1 This crushing appears very local, because on other occasions it was far less marked; and I do not regard it as in any way indicative of a fault, rather such as might be caused by melting of included ice-blocks or local settlements.