348 Seeley — Collocation of the Strata at Ely, 



seen with my own eyes and those of a hundred other men, and 

 proved with my own hammer and the hammers o± many friends, I 

 cannot but ask whether the Boulder hypothesis, coolly resting on 

 its icebergs, is one of those things so beautiful that it must be 

 true, and that the faults urged against it may be ignored? 



The facts appeared, and still appear, to me to prove (1) that 

 there is a sequence from Chalk to Kimmeridge-clay ; (2) that the 

 sands under the Gault may be connected with the adjacent sands in 

 the fields above the pit ; (-3) that indubitable slickenside was seen 

 in the vertical junction, forty-five feet high, between the Boulder- 

 clay and the Cretaceous beds figured in Geol. Mag. Yol. II. p. 532. 



Since my paper was written the pit has been very much altered, 

 for, by cutting away the Chalk, I saw exposed behind it the Upper 

 Greensand, and behind the Upper Greensand was the Gault, and 

 behind the Gault the brown sands, badly seen, and usually cut 

 through by a fault filled with Boulder-clay; and behind all, the 

 Kimmeridge-clay. So that compared with the section given in 

 Geol. Mag. Vol. I. p. 151, the section now is — 



Fig. 1. Section at Roswell Hole, near Ely, as seen May 28, 1868. 



i 



5| i 



Water. Chalk. p "" ^ 



Kimmeridge Gault. Boulder Kimmeridge 



Clay. Clay. Clay. 



This is parallel wdth the section in Geol. Mag. Yol. II. p. 582, and 

 at right angles with that at p. 530. There are several minor slips ; 

 one last year was exposed, and showed a smooth surface along its 

 visible face of 100 yards. It is apparently on the above or some 

 similar section that Mr. Fisher would ground his case. He also, in 

 the text, throws doubt on my identification of the clay under the 

 Upper Greensand as " Gault," but, in a note, says he has seen "the 

 Lower Greensand in sequence to this clay, which would make it 

 true Gault." If so why print the doubt ? Any one who pleases 

 may go and collect from the clay twenty or more of the most 

 characteristic Gault species. I did so in 1862 and again last year, 

 and anyone who pleases may see the claj'- resting on the brown 

 sands, as I figured it in 1865, and as Mr. Fisher saw it in 1867. I 

 think, then, we are agreed that there is a sequence through the 

 Chalk, Upper Greensand, Gault, and Brown Sands under the Gault. 

 But further on in the text, p. 56, referring to the cottage on the 

 bank, Mr. Fisher says, " I believe the Lower Greensand blocks 

 which occur on the north (? south) side hereabouts to be no more 

 in situ than the Chalk." Yery likely. They are strewn all down 

 the bank. Now in 1861 and in the spring of 1862, by removing 

 the superimposed Gault a large floor of sand-rock called Lower 



