The Section Exposed
in the Foundations of the New Admiralty Offices.
Proceedings of the Geological Association 1892
 Before describing this Section and its contained fauna, I wish to acknowledge the great obligations which I am under to the following gentlemen, without whose invaluable assistance these notes would have lost the greater part. of their importance and value, viz.: Prof. T. Rupert Jones, Messrs. A. S. Woodward, E. T. Newton, R. Lydekker, G..A.. Boulenger, B. B. Woodward, C. O. Waterhouse, and E. M. Holmes.
DESCRIPTION OF THE SECTION.
The Section was exposed in the excavation for the foundation of the new Admiralty Offices on the site of Old Spring Gardens Terrace, St., James' Park, in 1890. It was about 100 yards by 50 yards, and represented an aggregate depth of over 40 feet. Its greatest length was in a N.N.W. and S.S.E. direction: the present river runs about N.N.E and S.S.W.; so neither of the sides of the section coincided with its banks. The altitude of the N.N.W. corner is 23 ft. 6 in., and of the S.S.E. 14 ft. 6 in., above 'Ordnance Datum,' as measured on the western face of the Section shown. in fig. 2. The bed rock is London Clay, which falls to the South but still more so to the S.E., so that the district is naturally drained along this surface; the waters are,. however, to some extent held back by the peat bed H, thus originating the springs which give rise to the name of "Spring Gardens." The pumping machinery and drainage operations resorted to, to get rid of this water during building, were probably the most elaborate ever employed upon a similar occasion. Firstly deep channels were cut through the gravels into the London Clay along the northern face, and the waters diverted along the sides to the S.E. corner, where pumping went on day and night. Eighteen-inch piles, tipped and topped with iron, thirty feet long, touching each other, were driven by steam pile-drivers into the clay: the latter was then dug out, the space filled with concrete, and the foundations covered with plates of asphalt.
London Clay was quite black when wet, and in no instance showed the slightest sign of oxidation or staining, not even when overlaid by the highly ferruginous gravels. It was fairly fossiliferous, Nucula Witherelli occurring in seams, large Nautili very much flattened, some
dozen or so gastropods, and one or two foramenifera. But the fossil of the greatest importance
 is a leg bone of a bird, which Mr. Lydekker has referred to Proherodius Oweni, Lyd. This bird was probable the size of a heron, and presented such generalized characteristics as one would expect to find in an ancestral type of the Ardeidae, although the trochleae were probably of less equal length than obtains in the family to-day. Mr. Lyddeker added a description and figure of this, in an appendix to the British Museum Catalogue of fossil birds," which was then going through the press.
* Brit. Mus. Cat. Foss. Birds, pp. 363 and 364. 1891.
Fig. 1.Proherodius Oweni. (A) Anterior and (B) Posterior Aspects of the Right Tarso-Metatarsus: Nat. size.
Upon the London Clay rested a layer of boulders, which in the north end were for the most part flints of unusually large dimensions, some measuring eighteen inches by twelve or fourteen, generally quite undecomposed and unworn ; these were, accompanied by very large septaria from the London Clay, usually unaltered and fossiliferous. In one part of the section an area some forty feet square was exposed, where the boulders had been driven into the London Clay and all their tops planed off and striated. On the west side, the septaria, in addition to being stained to the colour of the iron-stained gravel and soft to the touch, upon being broken open revealed that the alteration had taken place to various extents, sometimes only for an inch or so, at other times right through the septarium. But the most remarkable fact was that, from this process, a secondary structure had resulted, with alternate layers of limonite and earthy  matter which in appearance simulated almost every variety of agate. None of the contained fossils were altered,
although the septa were unusually thin and scanty. ...
 ]T]he most interesting of the flints were those that had been used by man; of these there were some dozen plain flakes of various sizes; others were worked flakes, of which one lanceolate form foreshadows the well known Neolithic type, although the quality of its work is essentially Paleolithic. Some cores were very good, showing small parallel flaking; in others the flaking was much larger, and attained a length of three inches; all the worked flints from these gravels were deeply patinated, and some of the cores were water-worn.
The mammalia include Bos taurus, var. primigenius; Cervus elaphus, Cervus, sp. (small); Elephas primigenius; Equus cabalus;  Hippopotamus ambiphius; Rhinoceros sp.; a small Microtus. This latter species is very difficult to determine, owing to the approximation of its bones to those of the other species; there are however slight differences, and by comparison of these bones and teeth with the modern form, the probability points to it being M. agrestis. If so, it is the first time it has been found in the Pleistocene, at least in the Thames Valley....
 The Implements. The flakes are such as occur at all the valley sections, though upon the average not quite so large. Hollow scrapers are found in all periods: one found was not quite satisfactory; one apparent fabricator was ruder than the well-known Neolithic types, and deeply patinated. There was one leaf-shaped implement, which presages the Neolithc type, but the quality of the work was similar in every respect to the specimens I found in Reculvers Cliff; it, also, was deeply patinated. The most important implement, the small one referred to before, if found upon the surface might have been regarded as Neolithic; but lately I have seen very small implements taken from River drift, which were probably fish-hooks, bound at an angle to it a stick, similar to those our American friends are bringing to light.
The cores found point to the fact that flaking as fine as this was resorted to in those times; I have recently found similar cores in the old Darenth and Medway Valley drifts.
1. I do not consider that there can be any doubt as to the Pleistocene age of these older beds, for they contain the characteristic mammals, e.g., Elephas, Rhinoceros, and Hippopotamus, while Neolithic species, which are present in the beds above, are here absent. The Mollusca also include more characteristic Pleistocene (or extinct) species, than the law of percentages would demand. The occurrence of Betula nana also points to the same conclusion....