A HISTORY OF SUFFOLK to be no doubt that the Chelleen period preceded the Acheuleen in time. Hence therefore the Thames Valley gravels are older than those at Warren Hill ; the absence of the later types from the Thames Valley gravels pointing to the probability that during the period of the civilization represented at Warren Hill the Thames Valley was under w^ater, and therefore not habitable. This Warren Hill Period must have been of immense length. The ovates which have been found in such large numbers are by no means uniform in shape or appearance. Some are much more finely made than others ; and they vary also very largely in patina, the more finely made tending to be less patinated than those of coarser shape — some indeed being scarcely patinated at all. The great majority, however, are more or less deeply patinated ; and as already stated there is one type of patina, exceed- ingly common in implements from Warren Hill, which is rarely met with elsewhere — a curious mottling of surface, yellow or white spots on a blue ground, or blue spots on a yellow ground. Not only is the predominant patina special to Warren Hill, but there are two other peculiarities which occur in implements from that gravel which are rarely met with anywhere else. The first is that a very considerable proportion of them are differently patinated on the two sides of the ovate. Sometimes this difference is merely one of degree of change of colour, but in not a few cases the difference is more than this, one side being deeply patinated — with very marked colour change, whilst the other side is quite unchanged, and presents the original colour of the freshly chipped flint (which is in nearly all cases black). What does this mean ? In the first place it means that the patination had taken place before the stone reached its present position in the gravel ; for it is not possible that in a number of instances a stone lying in a sandy gravel should have had one side protected in such a way as not to undergo the same change as the other ; whereas it is easily under- stood that a stone lying on the ground for a long period of time will have its upper surface, exposed to all the varying conditions of weather and light, patin- ated ; whilst the under surface, protected as it is, will be much less changed — or even quite unchanged. The phenomenon is familiar to all who have examined flint implements from the African deserts. Here the stones have lain for countless ages with one side exposed to the hot African sun, whilst the other has been protected by the shade of the stone itself. So it must have been with these stones from Warren Hill, and we have thus specific proof that the patination took place before the stones were washed into the gravel. With regard to the length of time thus indicated we can only say that no neolithic stones, not even the very oldest of them, have a patina at all approaching that of the bulk of Warren Hill stones for depth and variety of colour. Yet we shall see presently that there are reasons for believing that the more ancient neoliths are of much greater age than they have hitherto been credited with. It would therefore seem that the Warren Hill implements — at any rate the older specimens amongst them — must have been lying on the ground for an immense — almost immeasurable — length of time before they were washed down into the gravels in which they are found. There is another remarkable point in connexion with implements from Warren Hill. In a large proportion of them the edges present chips varying 240
