CONTAINING- FLINT IMPLEMENTS, AND ON THE LOESS. 
26 . 
and I found gravel rising to a height of about 100 feet at Mantes, of 140 feet at Pont 
de l’Arche, and of above 100 feet near Rouen. 
In the valley of the Yonne the gravel attains a height of 66 feet at Pontaubert* ; but 
exact particulars are wanting of the terrace-gravels in this valley. Of the valley of the 
Marne, M. MiCHELixf observes that “on the heights around St.-Menehould there is 
a gravel containing the remains of the Elephant, Horse, and some other mammalia.” 
M. Corhuel states that the same valley higher up and that of the Blaise are covered 
with an oolitic gravel containing some remains of the Elephant, and names two small 
hills (buttes) near St. Dizier, and two near Vassy, which are capped by a similar gravel J. 
Valley of the Oise. — In this large tributary valley of the Seine, M. de Verneuil § has 
reported the discovery, at Precy near Creil, of a flint implement in beds of gravel contain- 
ing the remains of the Elephant, Deer, &c. In this instance the specimen was not 
found in situ , but was picked up amongst the gravel thrown on the adjacent line of 
railway. In April 1861 Sir Charles Lyell and I visited the ballast-pit whence the 
gravel was extracted. It is situated half a mile north from the Precy station, is about 
25 feet above the river, and presents a fine section of light-coloured subangular gravel, 
roughly stratified, 12 to 15 feet thick, and overlain by 5 to 10 feet of Loess. Some 
beds of the gravel are very coarse, and amongst the flint and tertiary debris are frag- 
ments from the oolitic strata and older rocks. The valley at this spot is about half a 
mile wide, and the hills on either side rise to a height of from 150 to 250 feet above 
the valley. In going over this ground some years since with the deeply lamented 
Edward Forbes, we found the rocks almost everywhere bare of drift, but I have a 
recollection of having met with traces of gravel with old-rock pebbles on a hill about 
80 feet high on the right bank of the river between Auvers and Beaumont. M. Graves, 
in speaking of the drift (Diluvium des vallees) of the Oise, observes that “ it ascends the 
slope of the hills to some height ” — “ some incontestable traces of it are sometimes 
found on surfaces of high platforms ” ||, but he gives no exact position or levels. 
M. d’Archiac, in describing the valley of the Aisne, the upper portions of the valley 
of the Oise, and their tributaries, states that the gravel (depot de cailloux roules, 
avec des blocs erratiques et des ossements nombreux des grands mammiferes) “ occu- 
pies the floor of the principal valleys, rises sometimes up their sides to a certain height, 
but very rarely extends over the adjacent high-ground plateau”^. Further on he 
mentions that between Menneville and Neufchatel (valley of the Aisne) the gravel rises 
65 feet afrove the river, and is about 16 feet thick, that between Voyenne and Marie 
(valley of the Serre) it is more than 130 feet** above the river — whilst at Guise (valley 
of the Oise) it rises 184 feet above the river, is 16 feet thick, and extends 1^ mile 
* Bull, de la Soc. Geol. 2 e ser. vol. ii. p. 683 (1845). + Ibid. vol. vii. p. 83 (1836). 
X Mem. de la Soc. Geol. de France, vol. iv. p. 270 (1841). 
§ Bull, de la Soc. Geol. de France, 2 e ser. vol. xvii. p. 555. 
|| Topographie Geognostique du dept, de l’Oise, pp. 529, 530 (1847). 
If Mem. de la Soc. Geol. de France, vol. v. p. 188 (1842). ** English feet are always given. 
MDCCCLXIV. 2 O 
