528 



terior date to the mounds of scoriae, which he is of opinion cannot be 

 ofgreat antiquity, on account of the facility with which their loose mate- 

 rials are removed by atmospheric agents. Other similar outbursts were 

 also described. 



The paper concluded with an account of the Great Runn, a di- 

 strict exclusive of the elevated tracts called '* the Bunnee and Islands" 

 of 7000 square miles. This singular region, as already described by 

 Capt. Burns, consists of a sandy flat, dry for the greater part of the 

 year, but during the prevalence of the south-west winds, con- 

 verted into an inland sea, passable however on camels. Capt. 

 Grant believes that its present oscillating position between land 

 and water, is due to an elevation of the Runn, and not a change in the 

 level of the seaj and in support of hivS opinion adduced the alterations 

 both of elevation and depression of land, by the earthquake of 1819. 

 He described also several extraordinary walls of rock, thrown up ap- 

 parently by volcanic action, sometimes assuming a dome shape, at 

 others segments of circles or straight lines. 



March 8. — Edward J. Chance, Esq., F.L.S., of Cook's-court, Lin- 

 coln's-lnn-Fields ; and Mr. Francis Looney, of Manchester, were 

 elected Fellows of this Society. 



The reading of a paper "On the Geological structure and phenomena 

 of Suffolk, and its physical relations with Norfolk and Essex ;" by the 

 Rev. W. B. Clarke, F.G.S., began on the 18lh ot January, was con- 

 cluded. 



The observations detailed in this memoir were made during 1827, 

 1828, and 1829, and are arranged under the he ids of the physical 

 features of the county, the geological structure, and the effects 

 produced by causes now in action. 



Physical Features. — Tiie general form of Suffolk is an oblong of 

 about 47 miles by 27, bounded on the east by the German Ocean, the 

 south by the river Stour, the west t)y the Ouse and Lark, and the north 

 by the Little Ouse and Waveney. It is impossible, says Mr. Clarke, not 

 to be struck with the fact, that whilst some of these river- courses have 

 an east and west direction, others flow from N.N.W. toS.S.E., and that 

 the coast section from Harwich to Orford, is nearly parallel with the 

 latter ; and he adds, if these observations be extended to Norfolk and 

 Essex, counties similar in geological structure, an accordance will be 

 found in the direction of their rivers and estuaries. 



How far these river channels may be due to dynamical action, 

 operating from below, the author thinks it is difficult to determine ; but 

 he is of opinion that when they are studied with reference to the proofs 

 of violent derangement in the north, east, and west corners of 

 Norfolk ; and the almost unequivocal evidence of disturbance on the 

 coast of Suffolk, there is sufficient reason for assuming, that the 

 drainage of Norfolk, Suffolk, and Essex has been induced by a violent 

 strain acting from below, and throwing the whole mass of the country 

 into a position, by which 1 200 square miles of Norfolk and 220 of Suf- 

 folk are drained by the Yare, and about 2U00 of the latter coui.ty at its 

 south-east corner. 



