Intellhence and Miscellaneous Articles. 397 



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materials carried to the sea, which even such minute quantities indi- 

 cate, is far greater than we might be led to imagine possible from 

 such fractions. It is only when we take into account the great vo- 

 lume of water constantly rolling along, and the prodigious multiplying 

 power of time, that we are able to discover the magnitude of the ope- 

 rations of this silent but unceasing agency. In the absence of more 

 accurate data for my calculations, for the sake of showing how large 

 an extent of waste is indicated by water holding no more solid matter 

 in suspension than is sufficient to disturb its transparency, I shall as- 

 sume that the Rhine at Bonn has a mean annual breadth of 1200 feet, 

 a mean depth throughout the year of 15 feet, and that the mean ve- 

 locity of all parts of the stream is two miles and a half per hour. 

 These assumptions are probably not far distant from the truth. I 

 shall take the average amount of solid matter in suspension to be 28 

 grains in every cubic foot of the water. 



** If we suppose a mass of water of a foot in thickness, 15 feet in 

 depth, and 1200 feet in length, we shall have a column across the 

 river containing 18,000 cubic feet j and 18,000 x 28 give 504,000 

 grains of solid matter in that column. 



*' A cubic foot of distilled water weighs 437,500 grains, and if we 

 take the solid matter as having a specific gravity of 2-50, a cubic foot 

 of it would weigh 1,093,750 grains. 



** If tlie river run with a mean velocity of two miles and a half in the 

 hour, 1 3,200 such columns would pass a line stretched across the river 

 every hour, and 316,800 such columns every twenty-four hours 5 

 (17()0 yards in a mile = 5280 feet, x 2^ = 13,200 

 and 13,200 x 24 =316,800.) 

 ** If 3 16,800 columns be multiplied by 504,000 grains, and the pro- 

 duct 159,667,200,000, be divided by 1,093,750, (the number of 

 grains in a cubic foot of the solid matter,) we have 145,980 cubic 

 feet of stone carried down by the Rhine past the imaginary line every 

 twenty-tour hours, — a mass greater in bulk than a solid tower of ma- 

 sonry sixty feet square, and forty feet in height. If we multiply 

 145,980 by 365, we have 1,973,433 cubic yards carried down in the 

 year; and if this process has been going on at the same rate for the 

 last two thousand years, — and there is no evidence that the river has 

 undergone any material change during that period, — then the Rhine 

 must in that time have carried down materials sufficient to form a 

 stratum of stone of a yard thick, extending over an area more than 

 thirty-six miles square. How much further back we may legitimately 

 carry our calculations, 1 leave it to those to fix, who consider that 

 there are any data to enable us even to guess at what epoch the 

 Rhine was difl^"eient from what it now is, either in respect of the vo- 

 lume or the velocity of the stream, in that part of its course at least 

 to which the present paper refers." — Jameson s Edinburgh Philoso- 

 phical Jimrnaly No 35.* 



* In Lond. and Edinb. Phil. Mag. vol. v. p. 211, was given an abstract 

 of Mr. Horner's paper, as read before the Geological Society, in which is 

 described the manner of performing the experiments, the results of which 

 are stated above. 



