Mr. SmealorCs Wvrks, &c. 105 



London clay, the Woolwich or Black- heath sand, the 

 Avlesburv limestone, the Chinch clay*, the Be Iford lime- 

 stone and clays, beneath it, the Barnack rag, and Colley- 

 weston lime and slate, the Foston blue clay, and the Maid- 

 well lime, all of which occur above the lias-clay; while 

 the coal series above the yellow lime (under the Sherwood 

 gravel as I suspect) and the important blue beds in the 

 yellow limestone series, are unnoticed : enough however is 

 contained in the above list, to show, that the late Rev. 

 John Michel ought to he ranked among those, to whom 

 geological science is indebted; and I take this method of 

 addressing myself to those, who may be now in possession 

 of his papers, to search for and communicate whatever de- 

 tails they may contain on the British strata, that will either 

 further explain the above communication to Mr. Smeaton, 

 or show the source, whence Mr. M. may have derived the 

 above particulars of the South British strata f: which 

 would be conferring a great obligation on 



Your obedient humble servant, 



1 2, Upper Crown Street, Westminster, JOHN FAREY, Sen. 



August 4, J 810. 



XV1H. An 



* Between the Bedfordshire orWobuin sand, and the Northamptonshire 

 limes or Bath freestone, which clay extends under almost all the Lincolnshire 

 fens, and most of those in Cambridgeshire and in Yorkshire. 



t P. S. Since writing the above I have been informed, that Mr. Michel, 

 whose death happened April 21, 1793, was at an early part of his life keeper 

 of the Woodwardian collection of fossils at Cambridge, which is thought 

 by some to be the very best general geological collection in existence, 

 though made near a century ago, owing to the great care and minuteness 

 with which the localities and attendant circumstances of the fossils therein, 

 are described: essential particulars, which 1 yet have appeared beneath the 

 attention of too many of our modern mineralogists and geologists, as it 

 should seem. It is not improbable, that a comparison of the fossil-; and 

 their localities, in this celebrated collection, first suggested the ideas of a 

 determinate order in the British strata to Mr. Michel, and the examination 

 of his papers is therefore a matter of the greater importance from the pro- 

 bability, that some such arrangement of the facts in theWoodwardian cata- 

 logue, may be found among them. Perhaps also, the present keeper of 

 the Woodwardian collection and papers will have the goodness to inform 

 us, whether any such arrangement of the British strata in a series is to be 

 found, or minutes of any such attempts, among the Woodwardian papers? 



Another scrap of paper, found among Mr. Smeaton's loose memoran- 

 dums, contains his experiments on twelve sorts of limestone, by dissolving 

 40 grains of each in aquafortis, and drying the clayey undissolved res;duum6 

 in the sun, the weights of which are a» follow, vi/. Grains. 



* Yellow lyas, of Axmyister . . . . . . 5^ 



Ditto with shining spangles (mica probably) . . ££ 



Yellow snake-stone, of Glastonbury . . . , . . 5 



Blue lyas, of Watchet .. .. .. .. 4f 



Ditto ofAberthaw 



Ditto of Bath 



Ditto of Axminster 



Yellow clump-stone, of Sherborne .. ., ., 3"" 



White 



4* 



