1;50 



developed. Nature has her frame-work and di'ess for her several 

 ages, and the artist who neglects this study of her must soon display 

 his want of a most necessary knowledge of his art. Much that 

 geology teaches is appreciable without any profound knowledge of the 

 science, and as I may not expect all I address to have made it their 

 peculiar study, I shall seek to render my observations interesting to the 

 many rather than the few. I am but a pioneer to localities others may 

 visit, who, by their more minute and scientific details, may fill up the 

 great hiatus ray inability and cursoiy survey must necessarily leave. 



I have selected as my present ramble localities easily approachable, 

 offering considerable diversity as a geological field, variety in its minerals, 

 and much interest in its historical records. 



Before proceeding with our survey, I must request permission, for the 

 benefit of those not geologists, to give an outline of the formation we 

 are about to visit. In England, and iu most quarters of the globe, 

 there is a great and extensive formation comprised of sands, clays, free- 

 stones, shales, seams and bands of coal, alternating with gritty sand- 

 stones ; limestone generally forming the basement : this formation, 

 wherever developed, has a sti-iking similarity iu its lithological character, 

 arrangement, and wonderful fossil flora : it is known as the carboniferous 

 series. Underneath, when conformable, we have variously disposed beds 

 of yellow and red sandstones, often appearing as flags or tiles, stones, 

 marls, or rather clays, difYereutly coloured, interstratified with a coucre- 

 tioning limestone called " cornstone,'' and in some parts a conglomerate 

 called " pudding-stone." 



This formation is said in some localities to extend 10,000 feet in 

 thickness, but in this respect it is exceedingly variable. Originally, from 

 the prevailing colour, these beds were called the " old red sandstone," 

 (to distinguish them from the " new red,") the lowest of the mesozoic 

 group ; latterly they have been re-named "Devonian," from their being 

 largely developed in Devonshire, but to my mind the old name is more 

 appropriate and significant, and I shall therefore adopt it. 



To the labours of Hugh Miller is due the interest attached to this 

 formation. Previously to his discovery of its icthyolites it held a doubt- 

 ful and indefinite position ; now, few afford better evidence for a 

 distinct and definite classification. Its stratification is exceedingly 

 variable, and sections, as developed in Scotland, and North and South 

 Devon, show little similarity. 



The palfeontologist, however, here interposes, and the evidence 

 afforded by disembodied organisms proves the position ; for however 

 variable may be the arrangement, nay, to a certain extent the compo- 

 sition, of a geological structure, the contemporaneous existence of its 

 fossils is conclusive proof of its identity for the purpose of classification. 



