Research over the past thirty years had already told us something o f the various groups occupying different parts o f Britain during the meso­ lithic period, which began around 8,000 b .c . with the onset o f a more

genial climate and the retreat o f the ice-sheets, and was brought to an end by the arrival o f neolithic farmers round about 2,500 b.c. Our knowledge o f the mesolithic hunter-fishers was still very slight before we started digging, because it was based in themain onstray finds, mostly o f worked flints, and on comparisons made between these and material from settlements excavated on the Continent, more particularly in Denmark (Fig. 2). It was known, for instance, that low-lying areas o f eastern England had been occupied during the Boreal climatic phase (c. 6,800-5,000 B.c.), before the temperature had reached its post-

glacial peak, by folk whose equipment resembled that o f the “ Maglemosian” hunter-fishers identified from widely separated points o f the north European plain from Flanders to the Ural Mountains. Indeed,

in 1932 the trawler Colinda had actually brought up a Maglemosian

spearhead o f stag ander from a depth o f 19-20 fathoms between the Leman and Ower Banks, some 25 miles from the Norfolk coast.