589 



the paper, and it is said that the former are parallel to the latter, 

 ranging S.S.W. and N.N.E. 



Jan. 3, 1838. — David Thomas Aristed, Esq., B.A., Jesus College, 

 Cambridge ; James Black, M.D., Bolton-le-Moors ; Alexander Wil- 

 son, Esq., Bryanstone- square ; and Major Henry Bullock, Harley- 

 street, were elected Fellows of this Society. 



A paper was read on the " Geological Relations of North Devon," 

 by Thomas Weaver, Esq., F.G.S., F.R.S., &c. 



The observations, which gave rise to this paper, were made during 

 the autumn of 1837, in consequence of the discussions which had 

 taken place relative to the position of the coal strata of the North 

 of Devonshire. The author states that he derived great assistance, 

 during his investigations, from the Rev. David Williams, who kindly 

 offered to be his guide. The survey, however, convinced Mr. 

 Weaver, that Prof. Sedgwick and Mr. Murchison were perfectly cor- 

 rect in placing the coal with the associated strata at the top of the 

 series, and in removing it from the transition systems to which other 

 observers had assigned it. 



The district, more particularly examined by the author, lies between 

 the parallel of Bideford and Chilhampton on the south, and that of 

 the Foreland (E. of Linton) on the north, and is bounded on the 

 east by the meridian of High Down (four miles west of South Mol- 

 ton), and on the west by the Bristol Channel. 



Before he proceeds to detail his own observations, Mr. Weaver 

 gives a comparative table of the subdivisions of the strata, exhibited 

 by Prof. Sedgwick and Mr. Murchison at the meeting of the British 

 Association at Bristol, in August 1836 ; and those employed by the 

 Rev. David Williams, in a section shown at the meeting of the 

 same body at Liverpool, in September 1837. These subdivisions, he 

 states, are essentially the same, though Mr. Williams considers the 

 coal strata as belonging to the transition systems. 



The subdivisions, first established at the Bristol meeting, are 

 adopted by Mr. Weaver, but he employs a nomenclature derived, for 

 the greater part, from the localities where the strata are well exhi- 

 bited. The following list contains the subdivisions in ascending 

 order. 



1. Foreland sandstone. 2. Linton calcareous slates. 3. Tren- 

 tishoe quartzy slates and sandstone, including the Combe Martine 

 limestone. 4. Morte slates. 5. Wollacomb sandstones, flagstones, 

 and slates. 6. Trilobite slates. 7. Wavellite schistus and lime- 

 stone. 8. Culmiferous shales (coal strata). 



The mineral composition, lithological structure, local variations, 

 and relative order of superposition of each formation are fully detailed ; 

 and the following inferences are given, as deducible from the whole 

 of the evidence, collected during the survey. 



That there is a general sequence of emergence from south to 

 north, or from the culmiferous shales (8) to the Foreland sandstones 

 (1), the dip being generally to the south. 



