I 49 ] 



Vlil. Geological Ohservations , on the Excavations of Valley s^ 

 the supposed Existence of numerous Lakes at former Pe- 

 riods luhere Valleys now exist, ivhich the Streams floiving 

 through them are said to have broken down, &c. : in Reply 

 to Mr. John Carr's Letter in the last Number, p. 452. 

 By Mr. John Farey. 

 To Mr. TiLLocH, — Sir, 

 Jljeforf. epithets so harsh, as " most lame and impotent 

 conclusion:" areapplieu to the wordsof any writer, it behoves 

 him who uses them, to endeavour fully to understand the 

 words commented upon ; but above all, to take care and quote 

 them faithfully. Having stated, page 2d2 of your last volume, 

 that I had for weeks and months together, daily contem- 

 plated valleys, " wonderfully distributed over the whole sur- 

 face of large districts, effecting a descending outlet or drain- 

 age to every part thereof:" 1 cannot pass over as immate- 

 rial, the alteration which Mr. Carr has made in substituting 

 " any" in place of the words " every part thereof," when 

 he quotes them (at page 432) for the purpose of "judging" 

 so hastily on my subsequent conclusions : because, by mark- 

 ing those words in italics, I expressly intended, to exclude 

 and deny the assumption which he makes just after, of a 

 succession of *' dWwwdX flats," existing generally in valleys, 

 the seats of a former chain of lakes ; the same having been 

 some years ago the opinion adopted (and it is a very old one, 

 as I have before observed,) by an able and scientific friend of 

 mine, founded on the appearances of. the gravel of one par- 

 ticular spot, and rocky cliffs below, in a long valej on 

 which, he and I have held frequent discussions, without any 

 conviction being brought to my mind, that a lake ever did 

 exist in the place alluded to, which is near to Leighton Bus- 

 sard in Bedfordshire : the opinion having, however, been 

 adopted, in the instance alluded to, by one, for whose abili- 

 ties and talents I have the highest respect, the subject has 

 constantly recurred to me since, without my having ever 

 seen any case, which could establish the probability even, 

 of the previous existence of a lake. 



When I wrote last from ShcfTitld, a most material part, 

 Vol. 34. No. 133. J?i/(/ 180". D at 



