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Leipsic beaches, it does not directly connect with a moraine at its eastern end, but a gap of ten miles intervenes. Terraces at Cleveland, Mr. Leverett thinks, make a connection between the eastern end of the beach and the western end of the moraine at Euclid, Ohio.

Temperature of the Sea.—The temperature of the English Channel was similar to that where the isotherm of 32° F. is now situated. The winter temperature can scarcely have been 20° colder than at present. The Mediterranean was perhaps 5° colder than now.

Temperature of the Land (air).—It does not appear that the climate of the lowlands of southern Europe can have been 20° lower than the present mean; 10° or perhaps less appear to have been the refrigeration in the Mediterranean region. The temperature at the southern margin of the ice-sheet was about 20° colder than at present. The temperature increased rapidly towards the south. Recent observations seem to show that throughout central Europe there was a period of dry cold, causing the country to resemble the arid regions of central Asia.

Geologists generally admit that there have been at least two glacial epochs, separated by one well-marked interglacial period. The closing stage of the Pleistocene period was one of cold conditions in northwestern Europe, accompanied by land depressions. After this came a genial climate with a union of the British islands among themselves and also with the continent. This was followed by a cold, humid condition.

Upham maintains that the whole of North America north of the Gulf of Mexico stood at least three thousand feet higher at the beginning of the glacial epoch than at present. Fiords were formed before glacial times and so can not be cited as evidence of high land during the glacial period. An elevation of land in the northern part of North America and Europe could not produce glaciation in their southern parts. The deflection of the Gulf Stream by the sinking of the Panama, Professor Geikie, argues, could not produce the conditions which prevailed during the glacial epoch. The Earth-Movement hypothesis, he believes, accounts neither for the widespread phenomena of the ice-age, nor for the remarkable interglacial climates. Some maintain that the warm interglacial period was produced by the rise of the Panama land, the sinking of the lands to the north, and the turning of the Gulf Stream from the Pacific into the Atlantic. Why then, asks Professor Geikie, do we not have such a climate now?