e A HISTORY OF SUFFOLK of similar conditions giving rise to the Lakenheath implements ; destruction of the valley, with excavation of the fen district ; and finally ' Mousterian ' man sitting on the side of the hill thus formed. When the conditions are appreciated the vast periods involved are almost beyond our comprehension. 6. After the implements of ' Mousterian ' man had been buried by th gradual accumulation of the 30 ft. (or more) of brick-earth, a recurrence took place of diluvial action, with the result that the present river-system repre- sented by the Lark and its affluents was established. The old river-valley with its gravels, the western side of which had already been destroyed, was now cut off from the high ground to the east, and its ridge-like character finally deter- mined. The ridge itself was at the same time cut into sections, and the beginning of such a cutting process at High Lodge swept the gravels capping the ridge at this point over the brow of the hill on to the top of the lower-lying but much more recently deposited brick-earth with its contained Mousterian implements. Before passing to the consideration of the Neolithic Period a few words must be said about the hiatus of time that is presumed tohave existed between the end of the Palaeolithic Period and the beginning of the Neolithic. There is a general consensus of opinion that in North-west Europe, at any rate, there was a lapse of time of indeterminate length, during which, for some reason not yet explained, large areas of Europe, including the British Isles, were unin- habited, and therefore presumably not habitable, by man. There has been a tendency amongst some archaeologists to call certain groups of implements which do not appear to find a place in any of the recognized periods ' Meso- lithic;' that is to say, between the Palaeolithic and Neolithic Periods. But the connotation of the word is so very large that it would require evidence of a far more convincing character than anything that has hitherto been brought forward to admit of its acceptance in scientific archaeology. For the present therefore we are justified in postulating the existence of a hiatus ; the Palaeolithic and Neolithic Ages being sharply defined from one other. During this hiatus man must have lived somewhere ; but as to the conditions of his existence we shall have to wait for knowledge until we have learnt a great deal more than we know at present of the Stone Age of the subtropical and tropical regions of the earth. The Neolithic Age If the Palaeolithic Period has presented us in North-west Suffolk with novel problems of great interest, the Neolithic Period in no way yields to it in the importance and the interest of the problems which it offers us. Here it is not, however, to the position in which the implements lie that we must look for the main factors of the case. Neolithic implements all lie on the surface or in the surface soil ; hence it is only exceptionally that we shall get help from position. It is the stones themselves that must be our study, their forms and especially their surfaces — the patination or other changes that have taken place on these surfaces. In stones from the gravels we saw that the study of patina might be of considerable service in clearing up problems ; but in their case the patina is only of secondary value, the chief element being the geological 248
