WATER IN THE EARTH.

Lake Wakatip Mail, Issue 2644, 28 January 1908, Page 7

WATER IN THE EARTH.

A REMARKABLE STATEMENT. In a discourse recently delivered at the Royal Institution in regard to ore deposits and their distribution and depth, Prof. John W. Gregory presents an astonishing view of the condition of water at temperatures above its critical point. It is evidently his opinion that the elements of water are not combined with each other above the critical temperature of liquefaction, for he says : "Water although its constituents may come from vast depths within the interior, is limited to a depth of perhaps only six or seven times the depth of existing mines. The lower limit is due to the internal heat of the globe. Now water cannot exist at a temperature higher than its critical point, 687 deg. F. "At depths below about 37,000 ft. the temperature would be above the critical point of water, which therefore, could not exist as such, Its elements would be given forth as separate gases from the slowly cooling mixture ; the gases would rise, and having passed into a zone with a temperature below the critical would combine to form water." The Professor has, a chemical expert tells us, confused the critical temperature of liquefaction, 358 deg. C., with the temperature of dissociation of water, which is probably about 2,500 deg. C. The only change which water undergoes at its critical temperature is the loss of its surface where it is in contact with a gas or vapour, no matter how great the pressure may be. If the view set forth in the quoted extract were true, the maximum temperature to be obtained by the combustion of hydrogen and oxygen would be 687 deg. F., which is near the boiling point of mercury. —"Science Sittings."