Germany were plentifully stocked, supplied its inhabitants with food and exercise. Their monstrous herds of cattle, less remarkable indeed for their beauty than for their utility, formed a principal object of their wealth. A small quantity of corn was the only produce exacted from the earth ; the use of orchards or artificial meadows was unknown to the Germans." All this, it will readily be seen, is highly consistent with a climate much colder than that of to-day.
The cause assigned by Gibbon for the amelioration of the climate of Europe is the cutting away of forests and the opening of the land for cultivation. The same process has popularly been supposed to account for the undoubted change which has taken place in Palestine and northern Africa. Meteorologists, however, agree that although forests conserve rain after it has fallen, they have no appreciable effect upon its amount. Having examined the meteorological records for various regions where forests have been cut off, or where they have been allowed to renew themselves after having been removed, students find no evidence that the climate has been altered. Moreover, as we have seen in the Lop basin, desiccation has taken place over broad areas where the trees have by no means been cut off, but, on the contrary, have remained standing, and have died for lack of water. The chief influence of forests appears to be that they keep the soil in a more uniformly damp condition, which prevents floods and makes the rivers and springs of more uniform volume. They also serve as a protection, and keep the air within them from being suddenly heated or cooled, thus preventing rapid changes of temperature. As to the relation of forests to changes of climate, the fact seems
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