147 



tint itself, without specific evidence of unconformity in each case, 

 can give no presumption of any weight as regards affinity or age." 

 Yet he states in the very next sentence, that he holds " that the 

 purple -grey colour accompanies an imconformity (in the district 

 under consideration)," and that he does not assume "that there is 

 an unconformity because some of the uppermost rocks of the Coal 

 Measures differ in colour from the main mass below." I cannot see 

 any real distinction between assuming that the "purple-grey colour 

 accompanies aminconformity ^^ and assuming the existence of a noncon- 

 formity on the mere evidence of the colour. Mr. Kendall admits that 

 some purple-grey sandstone at Blencow is of Yoredale, not White- 

 haven Sandstone, age, but thinks that this and other examples of 

 purple-grey Carboniferous sandstone, being outside the area em- 

 braced in his paper, have no bearing on the question. But surely, 

 as the Carboniferous Rocks of Cumberland form one series, and 

 show purple-grey beds on almost every geological horizon, any 

 theory not fully recognising the wide distribution of these beds is 

 extremely likely to be wrong. 



Mr, Kendall notices certain differences in detail between the 

 Bullgill and Aspatria sections, differences such as commonly occur 

 in sections of the same beds at collieries similar distances apart ; 

 but omits to see that the colliery workings in this case would allow 

 the existence of an unconformity to be iwoved — did one exist. 

 Could Mr. Kendall have demonstrated the existence of this 

 supposed unconformity from the evidence of these workings, he 

 would have shown the accuracy of his determination in this 

 instance, in spite of the remarkable coincidence between the 

 distances of the coals, etc., at the two places, tending to an 

 opposite conclusion. But, failing this, he has done nothing what- 

 ever to strengthen his case or to weaken my illustration. And as 

 no one of those best practically acquainted with the Aspatria 

 collieries seems ever to have suspected the existence of anything 

 abnormal there, but to have supposed the "Ten Quarters Coal of 

 Bank End Pit" to be the coal known by that name elsewhere, my 

 impression is that satisfactory evidence of this supposed uncon- 

 formity will continue to be "conspicuous by its absence." 



