Sir IT. E. Howorth— Dislocation of the Chalk. 299 



to the next higher portion of the series standing up nearly vertical, 

 having a dip of 70° to the south. . . . The same beds are seen 

 crossing the surface of the road to a length of nearly 70 feet, so 



that we must have as much as 60 feet thus set on end 



If we continue upwai'ds a little higher we find a still more 

 marked disturbance about the 500 feet level. Not only are the 

 beds tilted up, but they are actually inverted, so that instead of 

 dipping south at a very low angle they are dipping north at about 

 45°, having been turned through an angle of 135°. The date of 

 this disturbance is also indicated by these chalk beds actually lying 

 upon stratified Quaternary sand, which forms the mound on which 

 they were stopped. These phenomena indicate a powerful force 

 coming from the direction of the north, during a season in which 

 the lower levels were protected from its influence." (Proc. Geol. 

 Assoc, vol. v, pp. 267-8.) 



Again, he speaks of a quarry at Weaverthorpe, in which a mass 

 of chalk stands nearly vertical, and dips actually northward into 

 the hill. . . . The quarry has, in fact, been opened in a huge mass 

 which has broken off the rest, and has fallen or been forced over on 

 to its end. 



In another passage Mr. Blake remarks that " In some quarries 

 every fragment has its surface covered with parallel lines at different 

 levels, like a broken mass of basalt in miniature, or even like the 

 appearance of a worn massive coral. . . . This peculiarity has 

 been noticed before by Mr. Mortimer, who thought it was actually 

 due to coral growth ; that it is not, is of course proved by the total 

 absence of any real animal structure. . . . The slickensided chalk 

 may be found all over Yorkshire, but it is nowhere so remarkable 

 as near the change of direction of the line of outcrop — that is, a 

 little north of its highest elevation." (Blake, Proc. Geol. Assoc, 

 vol. v, pp. 265-8. The italics are ours.) 



These effects seem to me to be all due to one cause, and that 

 a very recent one, namely, the same cause which gave the 

 Yorkshire wolds their present contour, and which could be no other 

 than a powerful subterranean impulse. How is it possible for 

 anyone who has studied the work of ice in its native home to 

 attribute these effects jauntily, as Mr. Blake does, to the action 

 of ice ? " Geologists," he says, " will see in this [i.e. in the faulting 

 and bending of these solid beds of chalk], doubtless, another form 

 of those glacial forces which have strewed the bottoms of the 

 valleys, and in some instances hollows at high elevations with 

 boulders and clay." What fantastic writing is this ? As an 

 alternative in another case, Mr. Blake suggests that these contortions 

 and upheavals of solid chalk beds have been due to the wasting 

 effect of springs. Uniform itarian champions ought surely to 

 fall back on Mrs. Partington's mop. That would be a real 

 instrument of denudation. 



The large boulders referred to in my former paper as occurring 

 further south, are also found north of the Humber. Thus, Mr. Jukes- 

 Browne says : — " Large masses of chalk occur in the gravel ; one such 



