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STATED MEETING.— Saturday, November 29, 1862. 

 The Very Eey. Chaeles Graves, D. D., President, in the Chair. 



E. E. Madden, M. D., was elected a member of the Council in the 

 department of Polite Literature ; and the Eev. J. H. Todd, D. D., was 

 elected a member of the Council in the department of Antiquities. 



J. Beete Jukes, M. A., F. E. S., read a paper — 



On the Flint Implements found in the Grayel oe St. Acheul, neae 

 Amiens, and theie Mode of Occueeence. 



On my return from a Continental trip in August last, I halted for a day 

 in Amiens, in order to visit the locality where the well-known flint im- 

 plements have been found in some of the deposits that are generally asso- 

 ciated under the name of ^' the drift." These have been so thoroughly 

 explored and described by Mr. Prestwich, Mr. Evans, and others, since 

 the publication of M. Boucher de Perthes' work, that I could not hope 

 to make any new observations ; but I wished, if possible, to procure 

 some of the implements, and also to acquire that kind of knowledge of 

 the features of the neighbourhood and the " lie and position" of the beds, 

 which can only be acquired by personal inspection. 



In what I have to say, then, I appear rather as an expositor of Mr. 

 Prestwich' s papers, and as bearing witness to their accuracy and fidelity 

 to nature, than as an original investigator. The drift" of the north- 

 west of Prance is very different from the great northern drift of our 

 islands, which consists of materials derived from great distances, mingled 

 in confusion with those of the neighbourhood, and all driven pell-mell 

 over the country. In Prance, as was long ago shown by D'Arhtriac, 

 the gravels and sands of each river basin contain only those materials 

 that can be found in situ in the upper part of the basin itself ; and even 

 where two adjacent basins, like those of the Seine and the Somme, are 

 separated by a water-shed that is often very low and inconspicuous, there 

 is still no mingling of the "drift" of the two basins. This fact, toge- 

 ther with the additional one that the fossils found in these drifts" are 

 all fresh water, or terrestrial forms, prove that this "drift" is the result 

 of the river action, even where the deposits are far above the present bed 

 of the river.^' The fact that these rivers have excavated an additional 

 hollow in their valleys, 100 or 150 feet deep, and often one or two miles 

 in width, since the deposition of the gravels, seems to me perfectly 

 natural, since I have arrived at the conclusion that a far greater atmo- 

 spheric erosion has operated in the river valleys and over the whole sur- 



* Marine fossils occurring occasionally in the " drift" of the lower part of the river 

 basin merely show that the land stood at one time at a lower level, and that the sea accord- 

 ingly flowed farther up the valley than it does now. 



