The 'dawn man' is the most ancient human type in which the form of the head and size of the brain are known. Its anatomy, as well as its geologic antiquity, is therefore of profound interest and worthy of very full consideration. We may first review the authors' narrative of this remarkable discovery and the history of opinion concerning it.
Piltdown, Sussex, lies between two branches of the Ouse, about 35 miles south and slightly to the east of Gray's Thurrock, the Chellean station of the Thames. To the east is the plateau of Kent, in which many flints of Eolithic type have been found.
Fig. 63. Discovery site of the famous Piltdown skull near Piltdown, Sussex. After Dawson. A shallow pit of dark-brown gravel, at the bottom of which were found the fragments of the skull and a single primitive implement of worked flint (see Fig. 65).
The gravel layer in which the Piltdown skull occurred is situated on a well-defined plateau of large area and lies about 80 feet above the level of the main stream of the Ouse. Remnants of the flint-bearing gravels and drifts occur upon the plateau and the slopes down which they trail toward the river and streams. This region was undoubtedly favorable to the flint workers of Pre-Chellean and Chellean times. Kennard[(16)] believes that the gravels are of the same age as those of the 'high terrace' of the lower valley of the Thames; the height above the stream level is practically the same, namely, about 80 feet. Another geologist, Clement Reid,[(17)] holds that the plateau, composed of Wealden chalk, through which flowed the stream bearing the Piltdown gravels, belongs to a period later than that of the maximum depression of Great Britain; that the deposits are of Pre-Glacial or early Pleistocene age; that they belong to the epoch after the cold period of the first glaciation had passed but occur at the very base of the succession of implement-bearing deposits in the southeast of England.
On the other hand, Dawson,[(18)] the discoverer of the Piltdown skull, in his first description states: "From these facts it appears probable that the skull and mandible cannot safely be described as being of earlier date than the first half of the Pleistocene Epoch. The individual probably lived during the warm cycle in that age."
The section of the gravel bed (Fig. 64) indicates that the remains of the Piltdown man were washed down with other fossils by a shallow stream charged with dark-brown gravel and unworked flints; some of these fossils were of Pliocene times from strata of the upper parts of the stream. In this channel were found the remains of a number of animals of the same age as the Piltdown man, a few flints resembling eoliths, and one very primitive worked flint of Pre-Chellean type, which may also have been washed down from deposits of earlier age. These precious geologic and archæologic records furnish the only means we have of determining the age of Eoanthropus, the 'dawn man,' one of the most important and significant discoveries in the whole history of anthropology. We are indebted to the geologist Charles Dawson and the palæontologist Arthur Smith Woodward for preserving these ancient records and describing them with great fulness and accuracy as follows (pp. 132 to 139):
Several years ago Dawson discovered a small portion of an unusually thick human parietal bone, taken from a gravel bed which was being dug for road-making purposes on a farm close to Piltdown Common. In the autumn of 1911 he picked up among the rain-washed spoil-heaps of the same gravel-pit another and larger piece of bone belonging to the forehead region of the same skull and including a portion of the ridge extending over the left eyebrow. Immediately impressed with the importance of this discovery, Dawson enlisted the co-operation of Smith Woodward, and a systematic search was made in these spoil-heaps and gravels, beginning in the spring of 1912; all the material was looked over and carefully sifted. It appears that the whole or greater part of the human skull had been scattered by the workmen, who had thrown away the pieces unnoticed. Thorough search in the bottom of the gravel bed itself revealed the right half of a jaw, which was found in a depression of undisturbed, finely stratified gravel, so far as could be judged on the spot identical with that from which the first portions of the cranium were exhumed. A yard from the jaw an important piece of the occipital bone of the skull was found. Search was renewed in 1913 by Father P. Teilhard, of Chardin, a French anthropologist, who fortunately recovered a single canine tooth, and later a pair of nasal bones were found, all of which fragments are of very great significance in the restoration of the skull.