THE EARTH AS A MACHINE

Nelson Evening Mail, Volume LXIV, 9 January 1931, Page 2

THE EARTH AS A MACHINE

Addressing the Institution of Mechanical Engineers in London, Professor J. W. Gregory said the earth could be regarded as a machine, as it consisted of a combination of various parts and was moving through space and revolving around its axis in mechanical obedience to the major forces of the universe and without any conscious impulse or free will of its own. ' The combined rotation and revplution of the earth determined the weather and seasonal changes. The sea acted as the great regulator of the atmosphere, and counteracted all the disturbing agencies; for if too much carbon dioxide was taken from the air the bicarbonates in the water were dissociated and the sea breathed it forth Until the standard proportion was restored. If volcanic activity or forest fires added an injurious amount to the air, the sea absorbed the excess and retained it as bicarbonates. The atmo.sphere was thus maintained at the special composition necessary for human respiration. Land would be of no use to man unless most of its surface were sloping. All the land was constantly being lowered by wind and rain, and would in time be planed so level that the rain water would lie upon it, and collect in the hollows, and be removed only by the slow, chilling process of evaporation. But thanks to the constant interaction of the _ unequally weighted crust and the shrinking interior, the surface was being lowered in some places and upheaved in others. The instability of the crust, which we deplored when an earthquake devastated a province or killed 100,000 people or shattered picturesque Italian towns, renewed the slopes on which the habitability of the earth ultimately depended.