A HISTORY OF SUFFOLK lustrous blue ; (2) a lighter less lustrous blue ; (3) a deep and highly lustrous blue-black ; (4) a less lustrous black ; (5) a dull non-lustrous black ; (6) a thick more or less lustrous porcelainous white ; (7) a thin slightly lustrous white. And in addition to the more ordinary types of flint which undergo changes of surface in course of time, there are a considerable number of implements and flakes made of fine chalcedonic or jasperoid flint which decomposes with extreme difficulty. In most cases these have come down to us with little or no change, though there may be other evidence of their being of equal age with some of the most highly patinated of the implements made of ordinary flint. What evidence is there that pieces of different patinations, or different degrees of the same patination, are of different ages .? In answer to this it is only necessary to bring forward another feature frequently met with in this valley as elsewhere, viz. the occurrence on the same implement of the work of men of two different ages. In the best examples an implement of fine make which has undergone patination of a marked description has been carefully re-worked at some subsequent period ; and the re-worked surfaces are either unpatinated or have patination quite evidently less ancient than that on the original working. More often an implement of early Neolithic Period has been simply re-used at a later period without any care as to re-making. In such a case the old and patinated implement shows all round the edges the chips that have been detached when it was re-used ; such chips being either unpat- inated or having a different degree of patination from that on the original work. Sometimes more than two types of patination of human work are present on the same implement. From a study of a large series of such doubly patinated implements, much may be learnt as to the relative age of patinations. We now come to the most important point in connexion with the im- plements from this valley, and one which is wholly novel. This is the presence, on great numbers o( them, of scratches of various kinds — ^striae' to use the more scientific term. The importance of this phenomenon is very great. When we consider that flint is of a very high degree of hardness, even when of poor quality ; when we consider that most of the implements found in North- west Suffolk arc formed of flint of especially good quality, many of them being made of translucent chalcedonic or jasperoid flint ; when we find that flint of this quality will scratch with ease flints of less fine varieties, whereas nothing softer than quartz will scratch // ; and when we find that flints of this fine quality are themselves often scratched all over — the fact that this is so tends to excite our astonishment and make us ponder deeply on the causes that can have produced such a result. It will not be possible here to go into the abstruse questions which an inspection of these scratched surface-flint implements brings before the mind ; nor would an article in a county history be the proper place to enter on the highly controversial lines of investigation which would be necessary for their discussion. It will be well therefore to give only a short account of these striated implements, which, though occurring by thousands in this particular valley, are by no means confined to it ; they are found not only widely scat- tered over North-west Suffolk, but also in many other parts of England and elsewhere. Just as there are many varieties of patination of surface-flint implements — which can, however, be referred for the most part to six or eight main 250