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THE GEOLOGIST. 



rectified in your next number. You iiave embodied a foot-note in the text, which 

 makes it read that Dr. Fiedler's specimen was found on the confines of Holland 

 by a shepherd, which was not the case. I merely noticed it as a fact of ocular 

 demonstration of the formation of a fulgurite given in his work.— Yours, &c. 

 George D. Gibb." 



Geology of Wtgton, Cumberland. — " Sir, — I shall be greatly obliged to any 

 of your readers who can fin^nish me with information as to the geology of this 

 neighbourhood, the varieties of fossils, and the localities in which they are most 

 abundant.— I am, yours respectfully, Frank Dymond, Brookfield, near Wigton, 

 Cumberland." 



On a Pit-Section of Tertiary Strata at Woolwich. — By the Rev. 

 T. G. Bonney, M. a., of Westminster. — 'J The following descriptions of a section of 

 the lower tertiaries, at present exposed in a sandpit near Woolwich, may not be 

 uninteresting to some of the readers of The Geologist. The pit is situated close 

 to the road, between Charlton and Woolwich, and is divided by the railway. In 

 fact, strictly speaking, there are two pits ; one, the smaller, open to the road ; 

 the other, on the other side of the railway. It is of this latter that I intend 

 chiefly to speak. When I visited it two years ago, it was then deserted, but now 

 a considerable section has been exposed by working for sand. The section 

 exposed is as follows : — the measurements are only approximate, as I had no 

 instruments — (1.) Soil, containing many rounded pebbles, more especially in the 

 lower part (2 ft.). (2.) Yellowish-grey sand, with irregular rust-coloured streaks 

 (5 ft.). (3.) Sand and rolled pebbles. In this there are a few thin streaks or 

 traces of shells (3 ft.). (4.) A mass of shells and rounded pebbles. The shells 

 here are irregularly heaped together, as if by the action of the waves, just like a 

 great shell-bank. Their quantity is so great that, at a short distance, the seam 

 appears like a stratum of white rock. The shells are exceedingly brittle, and, 

 consequently, it is difiicult to procure good specimens, although the number to 

 choose from is enormous. I found about ten or eleven species, among which were 

 Melania inequinata, Cerithina funatum, Melanopsis fusiformis, Natica, Neritia 

 consobrica, N. globulus, Pectunculus, Cyrena, &c. The pebbles in this seam are, 

 periiaps, rather smaller than those above (2 ft.). (5.) A small band of grey and 

 yellow sand (3 or 4 inches). (6.) Small pebbles, sand, and shells. The shells as 

 before, but not quite so abundant. This stratum always formed a talus on the 

 cliff (10 ft.). (7.) Bluish and dark clay (13 ft.). The last 7 feet composed of 

 layers of different shades. The effect of this part, when seen from a little distance, 

 is very curious. The great number of parallel laminse of different shades look as 

 though the face of the chft' had been ruled with differently shaded inks. Shells 

 are plentiful in this, but very difficult to obtain perfect, there are not so many 

 varieties, apparently, as above. The most plentiful are, Melania inequinata (large), 

 Cerithium funatum, Cyrena cordata, and C. cuneiformis ; the last very abundant, 

 lying horizontally with the valves closed, as though they had been engulphed 

 while alive, or immediately after death. Oyster-shells also occur, especially in a 

 seam about 2 feet from the bottom of the bed. They are frequently of consider- 

 able size, and form conglomerated masses. (8.) Three seams of yellow sand, with 

 thin clay partings. This sand, I am informed, is used for the moulds in casting 

 brass (3 ft.). (9.) Grey sand, used in casting iron (12 ft.). Whitish sand, called 

 the ' silver sand,' used in making pottery. This bed is of great thickness, not 

 less, 1 should think, than 50 feet. 



" The above section is made in a line nearly at right angles to the river, and the 

 beds slope gradually upwards in that direction. In the other pit, by the roadside, 

 the section parallel to the road, shows only beds 9, 10, 8, and perhaps part of 7. 

 There also appears to be a small seam of pebbles separating 9 and 8 ; but with 

 regard to these I cannot speak with certainty, as they were high up in the face 

 of the cliff, and I had not time to make an accurate examination, indeed, I doubt 

 whether it could be accomplished mthout some risk. In this place the chalk has 

 been reached just below the level of the road. 



" The beds exposed in some other parts of the pits are a good deal bent ; in one 



lace they appear to be bent over a projection of the white sand, which seems to 



ave formed a sort of mound or shoal. 



