Antiquity of Man. Though, geologically speaking, man's appearance on the earth is but recent, various lines of evidence, historical, sociological, geological, and archaeological, all point to an antiquity of the human race that when estimated in years can only be called immense. While Chinese and Chaldaean records probably carry back authentic history beyond 2,000 B.C., Egyptian hieroglyphics go back to at least 3,000 years before our era. The science of language, in indicating the derivation of whole families of languages, such as those of Europe and India, from a common stock, also involves a great draft upon the bank of time. Bricks and pottery are found below sixty feet of Nile mud, which probably only accumulates at the rate of a few inches in the century, and rude stone weapons, belonging apparently to some pre-Aryan race, are present throughout India, In Switzerland pile-dwellings are found in the mud of the lakes in which, below remains belonging to the period of Roman dominion or iron age, implements of bronze and of polished stone occur at successively greater depths. In Denmark, in addition to extremely ancient mounds of shells and bones known as kjokken-modding ("kitchen midden"), successive layers of the peat are characterised by the beech, the chief tree of the country in Roman times as now, associated with iron implements, by oak associated with bronze, and by pine associated with polished stone or neolithic weapons. This points to the lapse of long periods marked by changes in climate. In England, France, and Belgium human bones and implements have in numerous cases been found in caverns under thick layers of stalagmite associated with the bones of animals either locally or altogether extinct, such as the wolf, hyaena, bear, horse, reindeer, and mammoth. These remains date backwards from a pre-Roman iron age through the ages of bronze and polished stone, when a Mongolian race prevailed in northwest Europe, through a period of chipped flint implements known as the reindeer period, from the abundance of reindeer bones, to the palaeolithic age, or period of the most ancient and rudest known chipped tools. Lastly, in the gravels and brick-earths of the rivers of the same area a similar succession is traceable, human implements occurring not only in association with mammoth, musk-ox and other animal remains, indicating cold conditions, but also under ice-borne detritus that marks at least the close of the glacial period. Though not as yet precisely estimable in years, these indications point to an antiquity which must at least be expressed in tens of thousands of years.