GEOLOGY. 2G1 



vocatiiig their origin from a chemical point of view. These sand- 

 pipes were most abundant in the disturbed chalk, and less so in 

 the solid strata. The latter allowed the water to get away by 

 means of joints and flint bands. The age of some of the sand- 

 pipes could be told by the material filing them, and by the un- 

 changed contour of the country. In the excavations attending 

 the sewage works at Norwich, much trouble was given by their 

 having to work through strata thoroughly saturated with water. 

 The same sort of strata standing above the water-level gave no 

 trouble whatever. The deduction was drawn that if so much 

 trouble ensued whilst working only twenty feet below the water- 

 level, the excavation of the proposed channel tunnel, under so 

 much more pressure, must necessarily be attended with great difli- 

 culties, Mr. Taylor gave an interesting statement of the manner 

 in which the wells were drained by the f)umping in the neighbor- 

 hood of Norwich, and showed they were affected according to 

 the different nature of the strata in which they were sunk. 



Mr. Godwin Austen mentioned several localities in Devonshire 

 where sand-pipes occurred in the sandstone rocks, and thought 

 that the chemical theory could not hold in cases like these, al- 

 though they might do so in chalk districts. 



Sir Willoughby Jones expressed his gratification at the papers 

 which had been read, and, as a Norfolk man, said he could thor- 

 oughly bear out the correctness of Mr. Taylor's views. It was a 

 very common thing for holes to be suddenly formed by the caving 

 in of gravel and sand into the sand-pipes. 



Mr. Taylor, in reply to Prof, Harkness, said that the upper and 

 lower boulder clays in Norfolk were very distinct. The former 

 were derived principally from the wreck of the lias beds, and the 

 latter from the lower chalk and oolite. One was of a dai'k-blue 

 color, and the other of an ochreous white. 



The next paper was by a French geologist, G. A. Lebour, on 

 the "Denudation of Western Brittany," read by Captain Galton. 

 There was also another communication by the same author, '* Notes 

 on some Granites of Lower Brittany." The section closed after a 

 paper on " Some New Forms of Grapfolites,'''' by Dr. H. A. Nichol- 

 son. This paper was read by the President, who stated there 

 could be no doubt that the fossil gi^aptoUtes were related to the 

 recent sertularia. 



The Extinction of tlie Mammoth. — A very interesting paper on 

 this subject was read b}' Mr. H. U. Ilovvorth. The various his- 

 torical notices in old authors of the mammoth remains in Siberia 

 and elsewhere were well condens&d. The usual idea was, that 

 the mammoth was a sort of huge mole,-- which rarely came to the 

 surface. This was the way their vast remains were accounted 

 for. Mr. Ho worth did not think the extinction of the mammoth 

 ought to be ascribed to the men of the early stone age. Prof. 

 Phillips and Prof. Boyd Dawkins made; some remarks on the above 

 paper, the former dwelling at some length upon the more popular 

 geological notions of the former conditions of northern geography, 

 and the hitter observing that Mr. Howorth had misunderstood 

 him. lie had never said that the extinction of the mammoth in 



