40 



very distinctly the structure and relations of the rocks ; the greater 

 number of the streams cutting through the limestone and millstone 

 grit, exposing the subjacent slate., and finally passing off on the de- 

 pressed strata of the coal measures. The author describes in detail 

 the phenomena presented in these several sections, and illustrates his 

 observations by sectional views and sketches. 



The structure of the country is very well displayed in the course of 

 the Ribble ; where, on the north, the slate first appears beneath pa- 

 rallel bands of limestone ; while on the south, the carboniferous 

 strata, the northern portion of which is horizontal, decline at a high 

 angle, thus indicating a vertical dislocation of about four hundred 

 feet. Besides this fault on the southern verge of the slate, another 

 still more important one in a parallel direction, may be traced across 

 the valley of Ribbles-dale, and over Malham Moor 5 — by which, strata 

 have been brought into immediate opposition, that in their original 

 place were separated by a thickness of more than five hundred feet. 

 Various facts are stated by the author in proof of this derangement, 

 and descriptive of the phenomena produced by it. 



The author subjoins to his descriptions some remarks on the strati- 

 fication of slate, and on the difficulty of discriminating between the 

 planes of general stratification, or dip, and those of the cleavage ef- 

 fected by a blow, — the latter of which are often disposed at consider- 

 able angles to those of the dip. He is disposed to think, that in the 

 fissile granular varieties of slate approaching to sandstone, the laminae 

 of cleavage may really be those of deposition ; since the surfaces are 

 frequently coated with mica, and the fossil remains are in a disposition 

 parallel to them. Besides this more general cleavage, however, the 

 slate is also traversed by other planes, oblique to those of the eleavage, 

 and less conspicuous, — to which the quarry-men give the name of 

 " Bate." The direction of these planes, though nearly alike in limited 

 spaces, is found to vary considerably in different portions of the same 

 tract ; and even the better-defined planes of the ordinary cleavage are 

 seldom parallel to each other throughout any great extent of country. 



A collection was exhibited at this meeting, of fossil vegetables, 

 chiefly from the Jarrow and Felling collieries, in the Northumberland 

 and Durham coal-field, presented to the Society by William Hutton, 

 Esq. of Newcastle-upon-Tyne ; with a catalogue describing the plants 

 according to the system of M. A. Brongniart, and drawings, with 

 some remarks by the donor. — The collection consists of specimens of 

 Calamites, Sigillaria?, Sagenarise, Stigmariea, Filices, Sphaenophylla, 

 Asterophylla, &c. ; and includes several undescribed confervae, leaves, 

 stems, &c. 



Jan. 18. — A notice was read " On the Occurrence of ' Chlorophasite' 

 in Basaltic Dikes, in Northumberland ; and of Carbonate of Strontian 

 in the Lead Measures at Fallowfield near Hexham," — by William 

 Hutton, Esq. of Newcastle-upon-Tyne. 



The author discovered * Chlorophasite ' in a basaltic dyke near the 

 river Coquet, about two miles N.E. of Felton 5 in the form of small 



