Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/495

 27. Sundridge Park. Here are the remarkable pits of indurated shelly gravel, described by Mr. Parkinson, Geol. Trans. vol. i. and p. 299 of this paper.

28. Between Sundridge Park and Camden Place, in the bottom of the valley, is a chalk pit covered with inferior sand of the plastic clay formation.

SECTIONS.

All these sections have been constructed on double scales, viz. a larger scale for the heights or vertical distances and a smaller for the horizontal distances.

No. I. General Section from Redriffe Tunnel to Knockholt beeches.

This is carried along the line of section marked in the map. The scale for horizontal distance is nearly the same as in the map. The colours also are the same, with the exception that the thick stratum of white sand which forms the lowest member of the plastic clay formation, is here distinguished from the other members of that formation by dotting it.

No. 2. Section of the pits upon Loam Pit Hill, see page 285. The strata are here coloured after nature; their resemblance to those of Alum bay in the Isle of Wight will instantly strike the eye on comparing this section with that accompanying Mr. Webster's paper, Geol. Trans. vol. ii.

No. 3. Section of the Great Sand Pits at Woolwich; described page 284. This section agrees with the preceding in its scale, in its colouring, and generally in the strata which it exhibits; but the partial changes which occur in different points of the same deposits will be likewise observed in comparing them together: the direct distance of these puts from those of Loans Pit Hill is rather more than three miles.

PLATES 14, 15, 16, 17, 18, 19, 20, 21, 22.

Views, Maps, and Sections to illustrate Dr. Mac CuIloch's paper on the Parallel Roads of Glen Roy.

Plate 14. A view in the upper part of Glen Roy, representing the terraces and the character of the valley at its commencement. The slope on the right of the picture is part of one of these terraces.

Plate 15. A view lower down, representing the coincidence between the terraces and one of the lines. The entrance of Glen Turit is seen in the distance.

Plate 16. A view from near Glen Fintec, comprising that part of the valley where the most perfect and uninterrupted continuity of the several lines is visible. On the hill which forms the distances of the picture they are also most perfect in their dimensions and forms.

Plate 17. A view lower down the valley. It serves to represent among other things the disappearance of a line where no assignable reason for its absence exists.