In the temperate regions the cold periods of the glacial epoch would be far more marked than the warm inter-glacial periods. The condition of things which prevailed during the cold periods would differ far more widely from that which now prevails than would the condition of things during the warm periods. But as regards the polar regions the reverse would be the case; there the warm inter-glacial periods would be far more marked than the cold periods. The condition of things prevailing in those regions during the warm periods would be in strongest contrast to what now obtains, but this would not hold true in reference to the cold periods; for during the latter, matters there would be pretty much the same as at present, only a good deal more severe. The reason of this may be seen from what has already been stated in Chapter IV.; but as it is a point of considerable importance in order to a proper understanding of the physical state of things prevailing in polar regions during the glacial epoch, I shall consider this part of the subject more fully. During the cold periods, our island, and nearly all places in the northern temperate regions down to about the same latitude, would be covered with snow and ice, and all animal and vegetable life within the glaciated area would to a great extent be destroyed. The presence of the ice would of itself, for reasons already explained, lower the mean annual temperature to near the freezing-point. The summers, notwithstanding the proximity of the sun, would not be warm, on the contrary their temperature would rise little above the freezing-point. An excess of evaporation would no doubt take place, owing to the increase in the intensity of the sun’s rays, but this result would only tend to increase the snowfall.[131] During the warm periods our country and the regions under consideration would experience conditions not differing much from those of the present, but the climate would probably be somewhat warmer and more equable. The proximity of the sun during winter would prevent snow from falling. The summers, owing to the greater distance of the sun, would probably be somewhat colder than they are now. But the loss of heat during summer would be to a large extent compensated for by two causes to which we must here refer. (1.) The much greater amount of heat conveyed by ocean-currents than at present. (2.) Our summers are now cooled to a considerable extent by cold aërial currents from the ice-covered regions of the north. But during the period in question there would be little or no ice in arctic regions, consequently the winds would be comparatively warm, whatever direction they came from.