Vietnam or Thailand ? Vote for the TOP Country of the Week !
Updated: May 18, 2025
Reviewing the various methods of calculation, Professor Chamberlin concludes that the time of the first spread of the ice-sheet is quite unknown, the second and greatest extension of the glaciation may have been between 300,000 and a million years ago, and the last ice-extension from 20,000 to 60,000 years ago; but he himself attaches "very little value" to the figures.
Now after it has been lying for some time, it will form a crust on top which is sometimes the effect of wind pressure and sometimes under favourable conditions of superficial glaciation. A similar condensation takes place at the bottom as the result of the work of gravity: a harder core will form. Between the two there is layer upon layer of comparatively softer snow.
In spite of the fact that glaciation causes swamps and lakes, the proportion of land cultivated in the glaciated areas is larger than in the driftless. In the glaciated area 61 per cent of the land is improved and in the driftless area only 43.5 per cent.
Traces of an earlier and independent glaciation have also been observed in some regions where the striation, apparently produced by ice proceeding from the north-west, is not explicable by the radiation of land-ice from a central mountainous region. The mountains of North Wales were recognised, in 1842, by Dr.
But the argument favoring it is well fortified and ably advanced, and if we add to the astronomical considerations involved, the physical proofs of a change in the earth's centre of gravity, caused by the excessive accumulation of ice about either pole, and the probable shifting of the Gulf stream to a southerly direction during the glacial period north, it is difficult to resist the conviction that the real cause of glaciation has been suggested in this theory.
This difference in form between the north and south sides of the peaks was almost wholly produced by the difference in the kind and quantity of the glaciation to which they have been subjected, the north sides having been hollowed by residual shadow-glaciers of a form that never existed on the sun-beaten sides.
Assuming, then, that relatively slight alterations of climate may cause the ice sheet to come and go, we may say that all the influences which have been suggested by the students of glaciation, and various other slighter causes which can not be here noted, may have co-operated to produce the peculiar result.
Simpson's place was essentially at the base station; and his consequent work as physicist and meteorologist prevented him from taking an active part in our sledge journeys. When he was recalled to Simla in 1912 his work was ably continued by Wright, our Canadian chemist, who, as I have said elsewhere, accompanied us south to make a special study of ice structure and glaciation.
The planet's in the middle of a glaciation, the land surface down to the fiftieth parallel is iced over solid. There is one city, ten or fifteen thousand, and the rest of the population is scattered around in settlements of a couple of hundred all along the face of the glaciers. They're all hunters and trappers.
Though they take land from agriculture, they probably add to the life of the community as much in other ways as they detract in this. Moreover glaciation diverted countless streams from their old courses and made them flow over falls and rapids from which water-power can easily be developed.
Word Of The Day
Others Looking