10,000 MILLION YEARS.

Hawera Star, Volume XLV, 16 October 1925, Page 10

10,000 MILLION YEARS.

EVOLUTION THEORIES. ESTIMATES OF SCIENCE. SECRETS OF EARTH’S AGE. Fascinating mysteries of the age of the earth and the secrets of its core were the subject of the presidential address of Professor Horace Lamb at the British Association at Southampton. His conclusion is that the final consolidation of the earth’s crust took place 1000 million to 10,000 million years ago. But for -the cooling process the higher figure should probably he multipled by 10—making 100,000 million years.

Professor Lamb, who is 75, spoke in defence of abstract science as a whole, pointing out that highly practical inventions had developed from researches at first purely intellectual. An American colleague, who was present at the Dayton trial, says that the extreme “literarists” of Tennessee don’t allow any margin. Their firm belief, based on the accepted testimony of an industrious professor, who worked it all out from the genealogical tables of the Old Testament, is that the world was created in the year 4000 B.C. The exact hour was 11 a.m. PRESIDENT’S CALCULATION.

It must not be supposed, however, that the new president of the Parliament of Science stated anything so "crude as that the world was “created” so many thousands of millions of years ago. What he said was this: “A comparison of the amounts of uranium and of the end-products associated with it has led to estimates of the time that has elapsed since the final consolidation of the earth’s crust. The conclusion is that it must he definitely between 1000 million and 10,000 million years. “The figure is necessarily vague owing to the rough value of some of the data; but even the lower of these limits is one which, geologists and biologists are, I believe, willing to accept as giving ample scope for the drama of evolution.

“We may say that physics has at ’ength amply atoned for the grudging allowance with time which it was once disposed to accord for the processes of geological and biological change.” Putting Professor Lamb’s mathematical thesis in another why, the period he suggests for the age of the earth, that is to say, for its consolidation into a fixed encrusted entity, harmonises with all the accepted evolutionary calculations of geologists and biologists. * This new estimate is based on radioactive arguments ; hut Professor Lamb would like to see even the outside limit of 10,000 millions years stretched. The difficulty imposed by the 10,000 millions’ limitation arises* from the assumed character of the interior of the earth. Professor Lamb’s doubts are engendered by accepting as a calculable hypothesis the view that the earth is made up of a central core of about four-fifths the external radius of high density, about that of iron, surrounded by an envelope of about the density of the surface rocks. Enormous a.s is the space of time mentioned, Professor Lamb points cut that within that time the great mass of the earth could hardly have cooled very much, from the temperature when it was in a state of fusion.

Indeed, the internal temperature would take to fall to half its original value a period of at least ten times the limit mentioned. Secrete Still*. Ale anti me, whilst the age of the earth is thus jdaced for the first time ,at least on a .scientific mathematical basis, the character of it.s innermost core remains a .secret, or at least —to quote the .president’s phrase—“somewhat mysterious. ’ ’ This region, of mystery extends from the centre to about one-fourth of the radius. One class of evidence points to the existence of so high a temperature as to suggest a plastic condition which would readily yield to shearing stress. Other evidence, however, indicates something like perfect elasticity, in the mathematical sense. The material, whatever is may he, is, says Professor Lamb, “under conditions far removed fro-m any of which we have experienced.” He suggests, ,ais a possible solution of the ■ difficulty, that “the material in question, under its special conditions, though plastic: under steady application of force (as, for instance, centrifugal force) may 'be practically rigid as regards oscillatory forces even when their period is so long as a day or a fortnight. This is as far as he regards it possible to go in speculation at present.