Qi Mr, Farcy's Geological Olservai'tons 



•with regard io the stratification of this important part of 

 England, may be cleared up. 



When I said (p. SI and 2S of your last Number) that ari 

 iminterrupted series of basset-ed^es of strata, dipping to 

 the SE, and ranging in continuity from SW to NE in 

 certain undulating lines conformable to the surface, " from 

 one sea to the other/' had been traced by Mr. Smith, and 

 shown on his manuscript maps, 1 spoke from an imperfect 

 recollection of some parts of his maps, and had forgot 

 some difficulties which he once mentioned having expe- 

 rienced, in tracing the strata across the flat country around 

 York : at v%-hieh time also, he was in the habits of meii- 

 tioniuii the oalite or ova-formed limestone of the Bath series; 

 and of Portland island in Dorsetshire, as belonging to the 

 same stratum; and as the late Rev. JMr. Michel also con- 

 sidered them, as I have mentioned, p. 103, of your 36lh 

 volume, and vol. i. p. 113, of my Derbys-hire Report, but 

 which now appears to he incorrect; and that the oalite of 

 St. Alban's-Head and PortIand-Is!e on the south coast, is 

 the same with that of Calne it) Wilts, Aylesbury in Bucks; 

 and Nevv-Malton, Helmslevj Kirby-Moorside, Pickering, 

 and Filey head SE of Scarborough, in Yorkshire, and is 

 situate within 100 yards (perhaps, and composed princi- 

 pally of chalk- marl) of the bottom of the chalk, greatly 

 aboAC the Bath-freestone* : and it seems, that besides the 

 disappearance of the upper of these important Oalites (the 

 Aylesbury Limestone,! under Alluvial Clay, from Stewkley 

 in Bucks, through all Bedfordshire, (see that article in the 

 Edinburiih Encyclopsedia,) and Cambridgeshire also, per- 

 haps, tilT its first exit from the Island near Hunstanton- 

 cliff in Norfolk, it makes no appearance, or where the lower 

 Chalk again enters the Island nearWainfleet in Lincolnshire, 

 or for some distance after the bottom edge of the Chalk 

 emerges irom the Fens near Walton, as we proceed north- 

 westward ; yet, in the hills near Dalby, Langton, &c. 1 saw 

 thickness enough of strata basseting, to account for this 

 Limestone Rock, that I had not time to search for minutely, 

 or to inquire what had been proved underground, in sink- 

 ing wells or otherwise, when I was in that county in 1807, 



* Do more than these lico parts of the I5ritish scries of strntn produce nva- 

 firmed /imff'iiiifi } a question I ask of your correspondents, from having seen 

 a very flat Kchinus lilted v/ith oaHic (like those of the Balh strata) said to 

 he liiought from I.inton Swiiidcn in Thrcslifield, ten miles N. of Skipton in 

 Yorkshire? The large botryoidal Pisolithus at Builine;-ii-ll one mile S. of 

 the mouth of the Wear in Durham, and in other situations, do not appear to 

 conipose regular strata, 1 believe, as the small pisolites do. 



Mr. Miclicl's '' verv fine white sand," vol. xxxvi. p. 104, seems to be that 

 d\:2 :it the foot of the red marl range, on Markhain-Moor, by the grear 

 Norlii iload. 



