40S Ml'. R. C. Taylor oji tJie Carho7iiferous Series 



posed to myself the honour of laying before the Geological 

 Society of London, when the interesting paper of Mr. Weaver 

 in the Lond. and Edinb. Phil. Mag. for August 1836, reached 

 me. I do not know how far what I have therein communi- 

 cated may influence the opinions of this experienced geologist 

 on the subject of the age of those coal deposits which I have 

 imperfectly defined under the denomination of transition ; but 

 for similar reasons to those which have led to Mr. Weaver's 

 communication in the Magazine, I am induced, through the 

 same medium, to state how I have arrived at a different opinion 

 to that which this gentleman entertains, on a very interesting 

 portion of American geology. I should greatly hesitate in 

 differing from an authority so deservedly eminent, and should 

 be disposed to adhere with much less tenacity to the views 

 which he has done me the honour to quote, but for the frank 

 admission that he has, unfortunately, not had the advantage 

 of seeing the district in question. However, I rejoice to per- 

 ceive that the geology of this country is attracting the atten- 

 tion of scientific observers, who have laboured so much and 

 so usefully in Europe, and who apply the experience acc]uired 

 in one quarter of the globe to the elucidation of unsettled 

 geological phenomena in another. 



Mr. Weaver inclines to the opinion, in support of which he 

 adduces more than one authority, that the immense series of 

 Pennsylvania rocks, amongst which are some inclosing nu- 

 merous thick seams of anthracitous, passing into bituminous 

 coals in certain places, belong altogether to the secondary car- 

 boniferous series or order. It is scarcely necessary to enter 

 into a detailed statement of all the evidence which has occa- 

 sioned a contrary decision, and which led to the classification 

 of the eastern coal-fields and the vast succession of conglo- 

 merates and red shales and sandstones, with the grauwacke 

 and the upper series of transition rocks. 



The arrangement I have adopted, for the present, may be 

 very shortly recapitulated ; commencing with the highest. 



1. The (almost) horizontal carboniferous series, forming 



the great western bituminous coal-field of this country, 

 whose eastern outcrop is the summit and the escarp- 

 ment of the Alleghany mountain range, through the 

 greater portion of Pennsylvania. All geological writers, 

 I believe, concur in denominating this a secondary 

 coal formation. This series includes the conglomerate, 

 or pudding-stone, and grit, resembling the millstone 

 grit, on which the series is unquestionably based. 



2. The Old Red Sandstone^ jjnd red shales, many thousand 



feet thick. The dip of its numerous beds, passing 



