In 1891, Prestwich presented at the Geological Society of London another paper, titled “On the Age, Formation, and Successive Drift-Stages of the Valley of the Darent; with Remarks on the Palaeolithic Implements of the District and on the Origin of its Chalk Escarpment.” In this paper, Prestwich (1891, p. 163) described a paleolith found by Harrison in a hole dug for the planting of a tree: “I have now seen the fine specimen. . . . It is 6 inches long by 3¾ in. wide, very flat and round pointed, and shows no wear. It more resembles one of the large St. Acheul types. It was found on the top of the soil last thrown out of the hole.” It is not clear what kind of sediments the tool was found in, but the manner in which Prestwich related the find suggests that he regarded it as a demonstration that the paleoliths were to be found not only on the surface, but
In addition to the paleoliths, Prestwich mentioned some of the cruder Eolithic implements. This brought some inquiries from William Topley, a fellow of the Geological Society and the author of a Geological Survey memoir on the Weald region. Harrison wrote in his diaries: “Mr. William Topley at the reading of the Darent paper said that he wished to know if there was any clear case of the flints being found in place. He added that the antiquity of the gravels in such an elevation [on the Plateau] was beyond question and certainly preceded the excavation of the great Chalk valleys and the present features of the Weald. In consequence of these remarks I went to the Vigo inn, and searched in and near the post holes dug for a fence. I found worked stones and thus recorded my first finds
Harrison also noted that in most cases his eoliths occurred in places where there were no paleoliths. To him, this indicated a different age for the two types of implements.
A. R. Wallace, who was greatly interested in Harrison’s finds, asked him for a copy of Prestwich’s Darent paper. Harrison forwarded the paper to Wallace, who later replied: “I read Mr. Prestwich’s paper with great interest, especially with regard to the rude type of implements, which I had never seen represented before. They are certainly very distinct from the well-formed palaeolithic weapons, and their having a separate area of distribution is strong proof of their belonging to a different and earlier period” (E. Harrison 1928, p. 370).
3.2 .4 More on the Geology of the Kent Plateau
In 1891, Sir John Prestwich presented a third major paper on the stone implements of the Kent Plateau. In this paper, delivered to the Royal Anthropological Institute, Prestwich pointed out that the Chalk Plateau of Kent, where Harrison found paleoliths and eoliths, is bounded by a large valley running across its southern border. According to Prestwich, this valley was scooped out by water action during the glacial period. The Kent Plateau, however, contained drift gravels like those present on the South Downs, the hills that still exist on the other side of the southern valley. Prestwich (1892, p. 250) stated: “as the flint implements are closely associated with this plateau drift, and are limited to the area over which it extends, we are led to infer the pre-glacial or early glacial age of the men by whom they were fabricated.” Just to clarify the reasoning, let us imagine ourselves in the Late Pliocene, looking south from the present North Downs and Kent Plateau. Instead of the valley now there, we would see the rising surface of the Weald dome (Figure 3.1, p. 88). At this time, according to Prestwich, the now-vanished dome uplands would have been inhabited by humans who made crude stone tools. Rivers and streams running down from the uplands flow north, depositing their gravels and sediments, along with stone tools, on the surface of the region now occupied by the North Downs and Kent Plateau. The rivers also flow south from the divide of the central dome uplands, to the South Downs.