THE AGE OF THE EARTH.

Taranaki Daily News, 10 September 1919, Page 6

THE AGE OF THE EARTH.

VARIATION IN ESTIMATES. The heat produced by radium is becoming of considerable importance in estimating the age of the earth. Discussing the matter at Auckland the other evening, Professor 0. Owen stated that radium was widely distributed throughout the earth's crust. One cubic mile of the earth's crust contained 371b of radium. The late Lord Kelvin assumed that the earth was once in a molten condition, and taking the known values of the thermal conductivity oi the crust, he arrived at the result that a period of 40,000,00(1 years had elapsed sin-:< the earth's crust solidified, ideologists, however, insisted, from the thickness of various geological strata, and other consideration that the earth's crust was from 100,000,000 to 150,000,000 years old. This discrepancy could not be accounted for, but the presence of radium in the earth's crust enabled us to extend Lord Kelvin's figure so as to reconcile it with the figures given by geologists. In fact, said the' lecturer, calculations of the age of the earth, based upon radio-active phenomena led to the result that the crust of the earth might be 500,000,000 years old. The discrepancy between this figure and the figure calculated by geologists was at present inexplicable. Biologists, however, hailed with pleasure the higher figure, for they required it to account /or the present, state of organic evolution. The lecturer stated that Professor j'oly suspected that the amount of radium in the earth was more than enough to keep it from getting cooler, and that in consequence there was going on in the interior of the earth an accumulation of heat which might some day burst its bonds and convert the whole "lube into a fiery mass. Tims it might be that, instead of the universe being, as it were, a clock slowly running down, its ultimate fate being the stillness of death, radium, acting as a rejuvenating force, would start the earth on its long journey of incandescence, cooling, solidification, and original evolution.