288 WELL-SECTION AT DALLINGHOO (sUFPOLK). [Aug. I9OI, 



Mr. A. E. Salter remarked that beds belonging to the Woolwich 

 and Eeading Series, etc., very similar to those found in the Southwark 

 well-section, were exposed in the deep drain-cuttings between 

 New Cross and Brockley, and also in the tunnel now being con- 

 structed between North and South Greenwich. 



With regard to the Dallinghoo section he must congratulate the 

 Author on his method of work. The absence of igneous rocks was 

 noteworthy, while those regarded as of Bunter or Carboniferous 

 origin were probably not derived directly from their parent rocks, 

 but secondarily through the Lower Greensand, Cambridge Green- 

 sand, or even the Crag. All the specimens shown might very well 

 have been derived entirely from the west. 



Mr. E. A. Maetin remarked that he understood that no specimens 

 were preserved of the material brought up in boring the Southwark 

 well. This was to be regretted, as the divisions between the 

 Tertiaries were often very obscure. Such was frequently the case 

 in other well-sections which he had examined, and if the material 

 from each depth quoted in the engineer's tables were carefully pre- 

 served and labelled, much obscurity would be saved. This led the 

 speaker to suggest a permanent resting-place for such material, in 

 a museum or elsewhere, his experience being that, even in those 

 cases in which the boring-engineers had gone to some trouble to 

 retain carefully labelled specimens, these very soon became neglected, 

 and labels became changed and specimens mixed, until they were 

 worse than useless. 



The Author said that, in his little paper, he had attempted to deal 

 with the facts ascertainable rather than to theorize. The similarity, 

 almost coincidence, of the well-section at Bankside, Southwark, 

 mentioned by Mr.H. W. Monckton, with that of Messrs. Jenner was 

 decidedly interesting, and pointed probably to the proximity of the two 

 borings. 



The thin stratum of acicular gypsum at Dallinghoo Well was so 

 large in extent, so brittle in character, and occurred in so hetero- 

 geneous a deposit, that it could hardly have been originally deposited 

 in its present state, but had most probably been formed since the 

 deposition of the Chalky Boulder-Clay. Prof. Seeley's suggestion that 

 the combustibility of the bituminous shale was due to the presence of 

 algse, while undoubtedly ingenious, was at variance with the ascer- 

 tained facts; for, although cephalopod and other molluscan remains, 

 as well as fish-bones and fish-scales, were abundantly present, no 

 marine plants had been detected after the most minute microscopic 

 investigation. In conclusion, he warmly thanked all the Eellows 

 for the kind way in which they had received the first geological paper 

 that he had read before the Society. 



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