ANNIVERSARY ADDRESS OF THE PRESIDENT. 



233 



on under the Bristol Channel to Cornwall, all east of the Mendip 

 Hills being now covered by the Secondary and Tertiary strata — 

 thus, I think, showing- that a widely spread floor of these Palaeozoic 

 rocks occurs under the extensive region of the southern half of 

 England, and which could as easily be shown to occur in the north 

 and in Ireland, but under different conditions. 



Now that the Ware Upper Silurians have been proved to dip to 

 the south, we may anticipate the occurrence of the more ancient or 

 lower series further north towards Cambridge, Huntingdon, and 

 Peterborough. Whether in their extension northwards they may 

 be of Scandinavian type we can only surmise, unless the Westmore- 

 land and Cumberland Silurians pass under the unconformable and 

 overlapping Carboniferous group of the Penine chain as a con- 

 tinuous floor or old surface to the south. 



Since the determination of the existence of the Devonian rocks 

 north of the Thames to Turnford, and of the Upper Silurian at Ware, 

 below the Cretaceous rocks at the depth of 800 feet, our views rela- 

 tive to the distribution of the Coal-measures have materially altered. 

 It is clear that all the stratified rocks between the Silurian and Gault 

 and the Devonian and Gault are wanting or not represented ; in other 

 words, the whole of the Carboniferous, Triassic, and Jurassic rocks, 

 and the Purbecks, &c. are missing north of the Thames to lat. 52° 10'. 

 This shows the great unconformable overlap upon the Silurian and 

 Devonian floor to the west. Had the sub-Wealden boring been 

 completed, the problem as to extension would have been solved. 

 Unfortunately for science this undertaking was never completed, 

 and the problem remained unsolved; the ancient land was not 

 discovered. We must rest content with the hypothesis of Mr. 

 Godwin- Austen as to the area where we should expect to find the 

 Coal-measures, probably ranging, as he suggests, under or north of 

 the North Downs. Life must indeed have been most abundant and 

 prolific in the Wenlock sea of the Ware locality ; for so rich in 

 fossils are these Ware beds that no less than 33 species were 

 obtained, all belonging to the Wenlock series, furnishing sufficient 

 data in themselves to establish and determine the age of the rocks 

 in which they occur. 



The five borings in the London area, or within the London basin, 

 within a radius of 20 miles, Ware being the furthest removed, taking 

 them in the order in which they were sunk, may be thus enume- 

 rated : — No. 1. Kentish Town, 1300 feet deep ; the London clay 

 passed through was 350 feet thick, the Heading beds 50 feet, and 

 the Thanet sands 15 feet, Upper Chalk 250 feet, Chalk-marl 30 feet, 

 Upper Greensand 10 feet, Gault 60 feet, and 190 feet of red sandy 

 rock believed to be Old Eed Sandstone or a condition of the Devo- 

 nian ; the depth passed through was 1300 feet. 



No. 2. The Crossness new well bore-hole about 1030 feet deep. 

 No London clay proper occurred in this sinking ; the alluvial clay 

 and gravel immediately below the ordnance level was 20 feet thick, 

 and rested upon the Woolwich and Reading and Thanet beds, here 

 about 100 feet thick, the Chalk 620 feet, the Upper Greensand 



