Reports and Proceedings — Geological Society of London. 571 



deposits, as well as the Lower, Middle, and Upper Chalk, with their 

 pateontological zones, are duly described. The Reading Beds next 

 receive attention. These consist partly of coarse sand and grit, with 

 small splinters of flint and with bands of the characteristic red- 

 mottled clay ; but westwards the deposit passes into a subangular 

 flint and chert gravel with a few Palaeozoic pebbles. An extra- 

 ordinary number of swallow-holes occurs in the district of Puddle- 

 town Heath and Bryant's Puddle, to which attention was directed 

 many years ago by the Rev. Osmond Fisher. Their occurrence in 

 the Reading Beds is attributed by Mr. Reid to the fact that the 

 strata overlying the Chalk comprise freely permeable sand and 

 gravel with bands of clay. The masses of imperisistent clay have 

 served to direct the rainfall to certain spots, whence it descended 

 into and dissolved the Chalk. 



The London Clay would hardly be recognized by one whose 

 experience was contined to the London area. In the Dorchester 

 region it consists of sand and sandy loam with septarian ironstone. 

 More interest attaches to the Bagshot Beds, on the extent and 

 composition of which much new light has been thrown by Mr. Reid. 

 By an attentive study of the small mineral fragments in unmistakable- 

 Bagshot Sands he has been able to trace the equivalents in coarse 

 gravels, which in some cases have been regarded as Drift ; more- 

 over, he has shown that westwards the Bagshot Beds overlap the 

 London Clay and rest directly on the Chalk. The evidence obtained 

 tends to confirm the view expressed by Mr. Starkie Gardner, of an 

 Eocene river flowing from the granitic and Palgeozoic districts of 

 Devon and Cornwall, and bringing coarse detritus as well as impure 

 china clay into the regions of Dorset and Hants. 



An interesting observation made by Mr. Reid is on the softening: 

 of Greensand chert. He noticed fragments so soft that they looked 

 like pebbles of pipeclay, though they soon harden on exposure. 

 This, as he remarks, "will explain the curious way in which the 

 fragments are sometimes dented by each other and pitted by 

 sand-grains." 



Among other subjects of interest are the Pliocene deposits of 

 Dewlish, which have been worked out very fully by Mr. Mansel- 

 PJeydell and Mr. Reid. The various superficial deposits, the clay- 

 with-flints, plateau gravels, and more recent alluvial deposits are 

 likewise described. 



S,EFOE,TS .A.3^JD :p:ROGE:EIDII>rC3-S. 



Geological Society of London. 



The first Meeting of the present Session, 1899-1900, was held 

 November 8th, 1899. W. Whitaker, B.A., F.R.S., President, in the 

 Ghair. The following communications were read : — 



1. "On the Cornish Earthquakes of March 29th to April 2nd,^ 



1898." By Dr. Charles Davison, M.A., F.G.S. ^ ! 



The importance of these three slight earthquakes lies chiefly in 



