28 
Mr. W. Pengelly on the Red Sandstones, 
ill v/liat way the latter have been operative, since, 1st. The stones are 
fragments of different kinds of rocks. 2nd. In no locality is every 
stone, whether of limestone or trap, found to be thus surrounded. 
3rd. In some localities every stone is free from any such investment. 
4th. The nuclei appear to have undergone no change of any kind 
since their inhumation. 5tli. If they have, by a direct centrifugal 
force, discharged the red colour, or, by a centripetal force, segregated 
the light- coloured and previously widely- distributed matter around 
them, or matter which has expelled the colour in any way, this force 
can have borne no fixed or constant relation to the mass of the 
nucleus, since spheres of the same size contain nuclei which differ 
much in dimensions, and conversely. 
In the Marls, however, the presence of stony, or, indeed, of any 
nuclei cannot be essential, as by far the greater number of the 
greenish spheres appear to be destitute of them, and stones are never 
found. Most of the nuclei which present themselves contain indica- 
tions of sulphur. Do these spheres "indicate," as Mr. Dawson 
suggests " the former existence of fossils whose forms have perished ? " 
I have dwelt thus long on the colours of the so-called Red rocks, 
in the hope that such of the members as have given attention to 
cognate questions — and I am happy to see several of my chemical 
friends present — may, at least, furnish some hints towards a solution 
of the problems which the phenomena suggest. 
Joints are numerous, and Faults are by no means rare. Except- 
ing those at Tor- Abbey Sands and immediately north of Babbacombe 
— figured and described in my last lecture-:- — and such as may, 
perhaps, exist in the more important valleys — which I do not now 
intend to discuss, — the faults are not generally of much importance. 
Those which I have observed between Dawlish and the Exe throw 
the country down towards the latter, that is, in the direction of the 
inclination of the strata ; and would, therefore, enhance any estimate 
of the thickness of the formation, based on the amount of the Dip 
and the extent of the section in its direction. On the other hand, 
the Triassic faults in the Torbay cliffs are in the opposite direction. 
As might be expected in a country where faults frequently occur, 
there are variations, in different parts of the district, in the amount 
and direction of the Dip, as will be seen in the following Table. 
The measurements have been taken with considerable care and in the 
following manner : when working in the field, I take with me a piece 
of school slate upwards of a foot in length and three or four inches 
wide ; this I lay on the surface of the bed so as fairly to represent 
its slope, and then gently pour a little water on its elevated end ; the 
direction in which this flows renders it easy, with clinometer and 
compass, to obtain reliable measurements of the amount and direction 
of the inclination. 
* " Transactions/' 1861—2, page 26, &c., fig 3 
