EARLY MAN division of the era into Stone, Bronze and Iron ages is convenient, but it fails to express changes of a more sweeping nature than these terms imply. Human time in Derbyshire, as in the north-west of Europe generally, is divisible into two well-marked ceons corresponding with the Pleistocene and the Recent eras of the geologist. The climate of the former alternated between the extremes of arctic coldness and sub- tropical heat, and these alternations were associated with changes as striking in the fauna and flora. Forms now confined to more northern and others to more southern latitudes, replaced one another with compara- tive rapidity, while some remarkable mammals, as the mammoth, woolly rhinoceros and sabre-toothed lion, have since become extinct. The con- figuration of the land also went through great changes, chiefly through glacial action, so that in many respects it differed from that with which we are familiar. During the Recent era on the other hand, the conditions as to climate, surface and life have undergone but little change and are substantially those of to-day. Although recent to the geologist, this period is so ancient that it includes all pre-historic time from the Neo- lithic to the early Iron ages and all subsequent historic time. It is a curious and well known fact that in Britain at least, there is no evidence that the one set of conditions gradually passed into the other. The dividing line appears sharp and well defined ; but for anything we know, it represents a period of unknown duration, possibly that of the last glaciation of the great Ice age. It falls across the Stone age of the archaeologist, dividing it into its Palaeolithic and Neolithic divisions. I. PLEISTOCENE TIME PALEOLITHIC MAN The Pleistocene deposits of Derbyshire, as may be seen upon reference to the section which treats of the geology of the county, are comparatively meagre. Glacial drift occurs here and there in sheltered places in the Peak, but it is more evident in the south, especially in the Trent basin, where it forms a discontinuous veneer. River-gravels and terraces, presumably of this age, also occur, but again mostly in the south. The limestone regions are famous for their caverns and fissures, and a few of the deposits ' fox-earths,' breccias, stalagmites, etc. of these have yielded Pleistocene remains ; but the smallness of the number is remarkable, owing perhaps to the circumstance that only a few of the caverns and fissures have been scientifically excavated. No discovery of a ' river-drift ' implement has been recorded in Derbyshire. A few years ago such a discovery would have been re- garded as impossible, for the opinion prevailed that these implements were confined to the south-eastern and southern parts of the island. The discovery of a quartzite implement of the type at Saltley near Birmingham in 1 890, however, makes it well worth the attention of Derbyshire archae- ologists to examine thoroughly their ancient river-gravels. It is remarkable that, so far as is known, no trace of Paheolithic 163
