92 SURVEY UNDER OFFICE OF WORKS CHAP, in 



lower beds. These lower beds may also cover up 

 members still lower in the series so completely that 

 they are nowhere exposed. 



When I wrote this paper I was buried in the 

 country without the means of reference to a single 

 book, and if I have omitted to refer to what has been 

 done by you and others in the same walk, it entirely 

 arises from forgetfulness or ignorance. The papers 

 referred to in notes were quoted from memory, and the 

 notes in the manuscript left with blanks for more 

 accurate detail when I got to town. Nothing could 

 be farther from my wish than to assume as my own 

 any idea started by another, especially by one whose 

 Principles of Geology strongly tended to make my 

 geological mind such as it is by first directing its 

 inquiries into proper channels, when, now some ten 

 years ago, I first began to dip into geology as a relief 

 from the irksome drudgery of mercantile concerns. 

 Had I no higher motive than my affection for the mere 

 book, that of itself would be sufficient to deter me 

 from such an attempt. 



Believe me, the opinion you express of my paper 

 has been to me a source of no ordinary gratification, 

 feeling as I do the value of approbation from so dis- 

 tinguished an author. I remain, dear sir, ever yours 

 sincerely, ANDW. C. RAMSAY. 



The following three letters of the same period 

 afford an indication of the relation of the Geo- 

 logical Survey to the dispute regarding Cambrian and 

 Silurian which was arising between Sedgwick and 

 Murchison : 



MUSEUM, 2<)tk December 1846. 



MY DEAR RAMSAY I put you in possession of notes which 

 have passed between Murchison and self touching Silurians, so that 



