2 1 2 Geological Society. 



leather, having a long string attached to it. A weight was sus- 

 pended from the bottle by a rope of such a length, that when the 

 weight touched the ground, the mouth of the bottle was at the de- 

 sired distance from the bottom of the river. The cork was then 

 removed by the string, and the instant the bottle was full it was 

 drawn up. 



The first set of experiments was made in August, at 165 feet 

 from the left bank of the river, and at 7 feet from the surface, 

 or 6 feet from the bottom. The Rhine was unusually low, and 

 the water was turbid and of a yellowish colour. The quantity 

 of solid matter obtained from a cubic foot of water, and slowly 

 dried, was 21*10 grains, or about T^-frm-th part. The residuum 

 effervesced briskly with diluted muriatic acid, was of a pale yel- 

 lowish-brown colour, smooth to the touch, and in appearance and 

 properties undistinguishablefrom the loess of the Rhine Valley. 



The second set of experiments was made in November on water 

 taken from the middle of the river, and about one foot below the 

 surface. A great deal of rain had fallen some time before, and 

 also fell during the experiment. The water was of a deeper yellow 

 than on the former occasion, but when taken up in a glass was not 

 very different in appearance. The residuum of a cubic foot weighed 

 35 grains, or the -i-g-.Vrnrth part. The author then enters into an ap- 

 proximate calculation of the medium quantity of earthy matter borne 

 down by the Rhine during 24? hours. He assumes that the annual 

 mean breadth of the river opposite Bonn, is 1,200 feet, the mean 

 depth 15 feet, the mean velocity 2-fr miles in an hour, and the 

 average amount of solid matter held in suspension to be 28 grains 

 in the cubic foot of water. From these data he deduces the result 

 that 145,981 cubic feet of solid matter are borne past Bonn every 

 24 hours. 



A paper was next read, entitled, " Observations on the Geo- 

 logical Structure of the Neighbourhood of Reading," by J. Rofe, 

 Esq., and communicated by Robert Hunter, Esq., F.G.S. 



This communication was accompanied by a collection of fossils 

 from the neighbourhood of Reading, and was prepared by the 

 author chiefly to point out the localities and geological connexions 

 of the specimens; but he also describes some beds belonging to 

 the plastic clay, which are not mentioned in the published accounts 

 of the district. 



In detailing the section presented by the Katsgrove pits, he 

 states, that the upper part of the chalk is perforated to about the 

 depth of a foot by tubular cavities resembling those made by the 

 Teredo in wood. The oyster-bed, which rests upon the chalk, he 

 says, is divisible into two parts, each about a foot thick, the lower 

 consisting principally of brown clay, and the upper of the sand 

 containing green particles. Above this bed the author observed 

 about a foot and a half of clay, and in the quartzose sand resting 

 upon it a layer of ochreous nodules. The account given by Dr. 

 Buckland of the strata above the one last mentioned*, the author 

 Fays is correct, with the exception of a thin bed of shells which 



* Geological Transactions, 1st series, vol. iv. p. 278. 



