Mr. Rose's Sketch of the Geology of West Norfolk. 171 



takes cognisance of. In a telescope of ten feet focal length 



and an aperture of one foot, a variation of a hundredth of an 



y 4 

 inch in A 4 corresponds to '0011 in the coefficient of ~- in 



8 



1 y % 



the expression for — , and to '00006 in the coefficients of-— . 



XX. A Sketch of the Geology of West Norfolk. By C. B. Rose, 



Fellow of the Royal Medical and Chirurgical Society of 



London.* 

 T^HE geological structure of West Norfolk has received 

 -*■ but little attention: it was first examined by the cele- 

 brated Mr. William Smith, many years since, during his pro- 

 fessional engagements in the county. The result of his re- 

 searches was made public by the appearance, in 1819, of his 

 geological map and section of the county; and were I not in 

 this place to bear willing testimony to the accuracy with which 

 he has laid down the course of the chalk range, and the out- 

 crop of the subjacent strata, I should be committing an act of 

 injustice to one who, from the originality of his views and 

 the great talents for observation he has displayed, is by uni- 

 versal consent acknowledged to be the father of modern 

 geology. 



Some distinguished members of the Geological Society have 

 at different times visited this portion of the county, the chief 

 object of attraction having been the cliff at Hunstanton, the 

 only natural section of the regular strata which we possess. The 

 information resulting from these visitations has been, I believe, 

 (not having been able to find anything further,) confined 

 within the limits of a note by the Rev. W. D. Conybeare, de- 

 scribing Hunstanton Cliff, in the • Outlines of the Geology of 

 England and Wales'; a description and section of that cliff by 

 Mr. R. C. Taylor in the Philosophical Magazine for February 

 1823 (vol. lxi. p. 81); and a notice of the chalk of West Nor- 

 folk, in a paper read before the Geological Society, May 2nd, 

 1823, by the same gentleman, and published in its Transac- 

 tions. There is also a brief notice of the strata, with a list of 

 the organic remains, in the ' Outlines of the Geology of Nor- 

 folk', published in 1833, by Mr. Samuel Woodward of Nor- 

 wich. 



The observations which follow are offered as contribution 

 towards the completion of a task, which, I trust, at some future 

 time will be undertaken by those who are more competent, 

 and have more leisure than myself. 



* Communicated bv the Author. 



Z2 " 



