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[ It has recently been shown that the growth of peat is a very slow process, and at the present time it is in many places either at a standstill or even in a state of retrogression. In the peat-mosses of Scotland, Lewis has traced nine successive layers, marked by different floras. The lowest of these and another at a higher level are distinctly of an arctic character, the intermediate forest beds, on the other hand, indicate periods of milder climate, when the limit of the growth of trees was at a higher level in Scotland than is now the case. From these facts it is certain that the peat-mosses of Scotland and northern England date back at least as far as the later stages of the glacial period, and indicate at least one mild interglacial episode, when the climate was somewhat warmer than it now is. (See Lewis, "Science Progress," volume 2, 1907, page 307.) Hence the statements of the French workmen, here quoted, do not possess much significance.]
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[ Cyrena fluminalis is very abundant in the gravels of an old terrace of the River Cam, at Barnwell, in the suburbs of Cambridge, and also in glacial gravels at Kelsey Hill in Holderness. It is a very remarkable fact that this shell, now an inhabitant of warm regions, should be so abundant in these Pleistocene deposits, in close association with glacial accumulations.]
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[ The implement-bearing deposits of Hoxne, in Suffolk, were investigated with great care by a committee of the British Association, and the results were published in a special and detailed report ("The Relation of Palaeolithic Man to the Glacial Epoch," "Report of the British Association," Liverpool, 1896, pages 400 to 415). The deposit consists of a series of lacustrine or fluviatile strata with plant remains, some being arctic in character, resting on Chalky Boulder Clay, and this again on sand. The Palaeolithic deposits are all clearly later than the latest boulder-clay of East Anglia, and between their formation and that of the glacial deposits at least two important climatic changes took place, indicating a very considerable lapse of time.
Mention may conveniently be made here of the supposed discovery of the remains of pre-glacial man at Ipswich, which appears to be founded on errors of observation. The boulder-clay above the interment is, according to the best authorities, merely a landslip or flow.]
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[ It has been suggested with a considerable degree of probability, that in Auvergne volcanic eruptions persisted even into historic times. The subject is obscure, depending on the interpretation of difficult passages in two Latin chronicles of the fifth century. The most obvious meaning of both passages would certainly appear to be the occurrence of volcanic eruptions and earthquakes, but attempts have been made to explain them as referring to some artificial conflagration, possibly the burning of a town by an invader. (See Bonney, "Volcanoes," 3rd edition, London, 1913, page 129.)]