PROCEEDINGS 



OF 



THE GEOLOGICAL SOCIETY OF LONDON. 



Vol. IL 1833—1834. No. 36. 



February '26. — Charles AUsop, Esq., of Broombriggs, near 

 Loughborough; James R. Hope, Esq., B.A., Fellow of Merton 

 College, Oxford, Royal Hospital, Chelsea ; and Williamson Peile, 

 Esq., of Whitehaven, were elected Fellows of this Society. 



A paper " On the Quantity of Solid Matter suspended in the 

 Water of the Rhine," by Leonard Horner, Esq., F.G.S., F.R.S., 

 was first read. 



The experiments referred to in this paper, were made by the 

 author at Bonn, in the months of August and November. The ap- 

 paratus which he used was a stone bottle capable of containino- 

 about a gallon, and furnished with a cork covered with greased 

 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 ^^j-j^^th part. The residuum 

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

 Jowish-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 -T-g-^VTnrth part. The author then enters into an ap- 

 proximate calculation of the medium quantity of earthy matter borne 

 down by the Rhine during ^^ 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-h- miles in an hour, and the 



VOL. II. G 



