1815.) On the Older Floetz Strata of England. 23 
lime-stone. It runs hence through the greatest part of Hereford- 
shire, generally preserving the same direction and dip.* It passes 
into Shropshire, where, from Mr. Aikin’s observations, it appears 
to pass under the coal-fields. It forms a great part of Cheshire ; 
and, according to Mr. Aikin, contains the salt springs of Droit- 
wich, &c. and the salt deposit of Northwich.t I have followed it 
into Brecknockshire and Monmouthshire. The lime-stones which 
shut in the coal-fields every where lie upon it. These I shall deno- 
minate mountain lime-stones, for the sake of distinction. They 
may be traced from a few miles S. of Ross to Chepstow, forming 
the beautiful cliffs which overhang the Wye, and in a conformable 
position with the subjacent sand-stone, dipping to the S.W. In 
general the sand-stone consists of fine grains of quartz, with a little 
argil, and a variable quantity of oxide of iron and mica : but in the 
hills, and on approaching the lime-stone, its constituents are diffe- 
rently disposed. At the bottom of a hill we often find the common 
red sand-stone ; higher up, a stratum of pudding-stone, containing 
rounded pieces of quartz, large masses of which in loose blocks 
cover the declivities; then there are beds of a whitish stone, the 
iron and mica disappearing, which makes a good building stone, 
but near these there is a thin bed consisting almost wholly of oxide 
of iron, and others almost entirely of mica. All these varieties 
occur ina hill near Ross, called Herol Hill. On the top of it the 
mountain lime-stone appears ; and about a hundred yards further a 
pit is open, when the lowest bed of the forest coal rises near to the 
surface of the ground. 
This red sand-stone formation is concealed near the Severn by 
the red marl rock and the Lyas lime-stone; but it appears again 
near Bristol, forming the basis on which the Somersetshire coal 
basin rests, of which Mr. Gilby has given an excellent account in 
the Philosophical Magazine for last November. I have seen it lying 
under the lime-stone near Axbridge, at the southern edge of this 
basin. ‘This formation would appear every where to rest upon the 
* Mr. Horner considered the Malvern Hills as affording countenance to the 
Huttonian theory. He observes, that the position of the stratified rocks seems to 
indicate that they were lifted up by a force from beneath. But if he had traversed 
the country to the westward of these hills, he would have found that the strata 
have generally a similar position, and even dip at a much greater angle, at the 
distance of 12 or 14 miles from the Malvern Hills. The absence of the stratified 
rocks onthe eustern side may be accounted for by supposing that @ submarine cur- 
rent flowed dowa the present Vale of Severn at the era when the rocks in question 
were deposited. Many indications may be found of the existence of such a cur- 
rent; but if none could be produced, surely the hypothesis is fully as admissible 
as the ejection of the granite masses from the abyss of Tartarus, 
+ Itis very strange that, after all that has been said concerning this salt forma- 
tion, we are yet without any satisfactory account of the stratum in which it 
occurs. Dr. Holland, in the first volume of the Geological Transactions, says, 
that it is subordinate to the sandsstone of the independent coal formation, Mr, 
Aikin, in thé same volume, informs us that they belong to the old red sand-stone ; 
and Mr, Horner, as lL perceive by the abstract of his late memoir on the south- 
eastern part of Somersetshire, given in the last number of the Annals, assigns 
them to the newer argillaceous sand-stone termed red marl, 
