410 Intelligence and Miscellaneous Articles. 



entrance, and forms, as it were, a cutting in the line of rocks which 

 border the valley on this side. It is by descending this way, that 

 the traces of polish may be observed on both sides of this species of 

 defile, but chiefly on the right side. There are very large blocks 

 there, and also masses of flattened rock, which seem to be a part of 

 the sandstone layers, or to have been but little moved from their 

 position. Upon examining their surface, we see that it is polished, 

 and even presents indications of broad furrows, the resemblance of 

 which to the diluvian furrows of the Alps or of Scandinavia, it is 

 impossible to mistake. A circumstance which precludes any doubt 

 that the marks are owing to the action of masses of water, is, that 

 they are directed according to the declivity of the defile, and fall 

 towards the interior of the central valley. 



Upon examining the surface quite near, we see no fine grooves 

 as we do on the granites and gneiss of the Alps ; nor is there any 

 reason to be surprised at this, because these sandstones, not being 

 formed of grains, which are strongly agglutinated together, were 

 not adapted for receiving and retaining very fine grooves. The 

 polish is also visible on the largest blocks of sandstone ; there are 

 several flattened, which are rather sunk in the earth or lie above it 

 on their broadest side, which is nearly horizontal and rugged, whilst 

 the superior surface is polished ; by a close examination, we find 

 that the polish is not owing to the friction of these masses against 

 each other or against the earth, but to the action of the waters. 



On the north anticlinal of the valley of Franchard, on the side 

 opposite to that I have just mentioned, we find another little defile 

 at the spot where the mass of blocks called Roche-qui-pleure is 

 situated : there the polish is still visible, but only upon some blocks 

 having the position already described ; several amongst them show 

 on their sides circular and rounded cavities, which appear to me to 

 have been caused by a whirling of waters ; they seem to have fol- 

 lowed the declivity of the land in its present configuration, and to 

 have been precipitated towards the middle of the valley. It would 

 have been interesting to see the disposition of the tracesCat the very 

 bottom of the valley ; but it is impossible, for the ground is covered 

 with sand and vegetable earth : there are very few blocks ; the 

 greater number of them are in heaps, crowning the two crests. 



This valley of Franchard may be compared to a cutting hollowed 

 by the waters in the high plain of sandstone which forms the 

 western part of the forest, and the level of which is very much 

 higher than that of the town of Fontainbleau. The mean direction 

 is from the east 10° south, to the west 10° north ; this is the gene- 

 ral direction of the numerous lines of hills covered with blocks, and 

 disposed in the form of bands extended in the same direction ; the 

 most prominent type of this disposition is the small chain which 

 extends from the Sablons to near Milly, and the different rings 

 (anneaux) of which bear the names of Rocher-de-bon-Ligne, of the 

 Salamander, of Trape-charette, &c. 



As M. Elie de Beaumont has so judiciously observed, these bands 

 take the direction W.N.W., which the Seine follows before recei- 



