On the occasion of a late visit to Abbeville, I noticed a fact which appears of sufficient interest, as bearing upon and confirming one of the points treated of in my last paper, to induce me to submit a short notice of it to the Royal Society. It occurs in a tributary valley to that of the Somme, but necessarily forms part of the general phenomena affecting the whole basin The small stream (the Escardon) which joins the Somme at Abbeville flows through a narrow chalk valley extending a few miles north of Abbeville. Three miles up this valley is the village of Drucat; and on the hill above the village, and about 100 feet above the stream, is a small outlier of high-level gravel which I have before described, and which is remark able for the number and size of its sand- and gravel-pipes penetrating the underlying chalk. One of these which I measured was 22 feet across at the top and 18 feet at a depth of 30 feet, and I estimated its depth at not less than 100 feet from the surface. It was filled in the usual way with sand and gravel in vertical cylindrical layers. M. Boucher de Perthes has two flint implements which are reported to have come from the pit; but I never myself found any there, or any mammalian remains. The sand and gravel is clean and light-coloured, and very similar in character to some of the beds at Menchecourt, and in so far has the appearance of a fluviatile gravel, and, like it, is overlain by a variable bed of loess. This bed was supposed to form an isolated outlier; but on my last visit I found another bed, though of coarser materials, on a hill of the same height on the opposite side of the valley, above l’Heure. The valley at the foot of the hill on which the Drucat gravel is worked is about a quarter of a mile wide. A lane leads direct down the slope of the hill from a point near the gravel to the valley; and a roadside cutting exposes a section of calcareous tufa or travertin several feet thick, and containing in places numerous land shells, of recent species, and traces of plants. Half a mile beyond, the bed is of sufficient importance to be worked for building-purposes. This bed is overlain by the valley loess, and is in places intercalated with it; it commences a few feet below the level of the gravel at about 70 feet above the valley, and continues to near the foot of the hill. Now it is well proved that in all purely chalk districts the line of water-level proceeds from the level of the streams and rivers traversing the disrict, in a slightly inclined and continuous plane rising on either side under the adjacent hills with a slope varying from 10 to 40 feet in the mile, the latter being an extreme case. If we take a mean of 20 feet, as the gravel-pit is not above one-third of a mile from the valley, the rise in the water underneath would not probably exceed 10 feet above the level of the stream. The chalk formation is so generally fissured and permeable that I know of no instance of a line of water-level or of springs occurring above the general line dependent upon the level of the adjacent rivers. It is also well known that strong springs are common at the foot of the hills along many of our chalk valleys, as, for instance, that at Amwell, those at Carshalton, and many along the valley of the Thames. These springs are more or less calcareous, often highly so.