TRANSACTIONS OF SECTION C. 575 



111 conclusion the author pointed out the difficulties in understanding the prin- 

 ciples of Professor Hull's classification. lie also showed that Professor Hull's use 

 of Jukes' and Griffiths' names and terms, in a sense different from that in which 

 they were understood by those authors, had introduced confusion. 



6. Note on the Range of the Lower Tertiaries of East SuffoUc. 

 By W. H. Dalton, F.G.S., of the Geological Survey of England. 



The Crags and Drifts of East Suffijlk prevent more than an approximate delinea- 

 tion of the outcrop of the Chalk from beneath the Lower Tertiary beds. 



The London Clay disappears from the surface a little west of Orford ; but the 

 deep boring at Sir E. Lacou's brewery in Yarmouth, made in 1840, passed through 

 170 feet of estuarine deposits, and then no less than 305 feet of London Clay and 

 51 of Reading Beds before reaching the Chalk. There could therefore be hardly a 

 doubt of the continuity of the Eocene beds between Orford and Yarmouth, although 

 their boundary-line might be for some part of its length outside of the present 

 coast ; indeed, in published maps, most of the interval is coloured as Chalk. 



The inhabitants of Suffi:>lk are, however, awaking to the disadvantages of a 

 water-supply derived from ponds and sewage-tainted sands, and consequently 

 Artesian wells, carried down into the Chalk, are increasing in number. 



The accounts of these wells (which will duly appear in the Memoirs of the 

 Geological Survey) give the following indications of the position of the outcrop of 

 the Chalk :— 



At Easton Park, Framlingham, Beccles, and Norwich, the Chalk is covered 

 directly by Crag or Drift. 



At Woodbridge, Saxmuudham, Bramfield, and Yarmouth a greater or less 

 thickness of Lower Tertiary beds is present, and their boundary is probably three or 

 four miles inland from these points. 



At Hoxne, a few feet of ' green clay ' lying directly on the Chalk may possibly 

 be an outlier of the Reading Beds. 



The Lower Tertiaries, thus outlined, possess no special interest, except that, beino- 

 impervious clays, they cut off impure surface waters, and are easier to bore through 

 than the loose sands, &c., overlying them. 



The plane of the Chalk surface, whether under or beyond the Lower Tertiaries, 

 is sufficiently uniform to render calculation of its depth in any part of the district 

 an easy process. In the Bramfield boring, the latest of the series, the Chalk was 

 reached at 48 feet below the Ordnance Datum, calculation from the three nearest 

 points — Beccles, Framlingham, and Saxmundham — indicating 52|- feet. 



FRIDAY, AUGUST 27. 



The following Reports and Papers were read : — 



1, Sixteenth and Concluding Report on the Exploraiion of Kent's Cavern, 

 Devonshire. — See Reports, p. 62. 



2. Report on the Exploration of Caves in the Sotdh of Ireland. 

 See Reports, p. 209. 



3. Report on the Viviparous Nattire of the Ichthyosauria. 

 See Reports, p. 68. 



