Nelson Evening Mail. SATURDAY, MAY 15, 1909. RADIO ACTIVITY. WHAT RADIUM "HAS REVEALED.

Nelson Evening Mail, Volume XLIII, Issue XLIII, 15 May 1909, Page 2

Nelson Evening Mail. SATURDAY, MAY 15, 1909. RADIO ACTIVITY. WHAT RADIUM "HAS REVEALED.

NOT the. least interesting, and, in all probability, the most important, ecientihc developments o£ the present day are those connected with radium, or rathor radio activity with radium as its chief centre. The idea that it has revolution, ised science in the general sense of the word is erroneous, but it has opened up stupendous avenues of knowledge about the material universe. Its 6tudy is being pursued with the utmost keenness by an enthusiastic group of investigatoris. The developments in this branch of science are particularly interesting to Nelsonians, because of the fact that Professor Rutherford, an old boy of Nelson College, who now occupies the Chair of Physics at the Manchester ' University, lately won the Nobol * rize for his achievements in this, field. The subject has attracted distinguished men of science like Sir William Ramsay, Sir William Haggins, and Dr Grigor. In the first instance it was the chemists and physicists to whom it made its strongest appeal, but gradually its importance to other branches of science is being perceived. At last- year's meeting of the British Association Professor Joly made the effect of radium upon geological formations the theme of his geo'sidential address in the geology section. The developments in this branch of science have been noted in the papers, and most of thorn have appeared in the "Mail," but up to the present little of a comprehensive nature dealing with the later developments has been written. A book has just been issued in Murray's "Progressive Science Series" caHed "The Interpretation of Radium," by Fred?rick Soddy, M.A., independent lecturer in physical chemistry and radio activity in tho University of Glasgow. Mr Soddy, it is stated," has conducted original research on his own account, and in collaboration with Professor Rutherford. H- is_ recognised as one of the leading authorities on radio activity, .md he possesses a happy faculty of lucid exposition. In. the course of his work Mr Soddy insists that the new facts of radio activity do not conflict with old basic theories" t>f chemistry and physics. "Radio activity," he 6ays, "is a new primary science owing allegiance to neither physics nor chemistry, as those sciences were understood before its advent, because It is concerned with a knowledge of| th? elementary atoms, themselves of a character so fundamental and intimate that the old laws of physics and chemistry concerned almost wholly with external relationship, do not, suffice. Physics and chemistry remain almost unchanged where thoy were, and radio activity so far at is is concerned with the correctness of their principles has. as a matetv of fact, given to tho

Id laws and theories a fuller and truer ignificonoe than they had before." Mr kjddy tJwn goes on to put facts before he reader which affirm his contention, kdio-activity, it has been shown, enters ito a new region hitherto unexplored by homist3 and physicist*. It deals, not fith tab changes in the relationship of itoms, but in the atoms themselves. So far as is known, only certain elenents, such as uranium, polonium, thoium (from which gas mantles aro made), md radium itself are known to be ra-lio-active; but others, perhaps all, may possess radio-active properties, though iheir action is so slow and feable that it cannot bs attracted, the four main affects of radio-activity are given as [1) That radio-active substances affect photographic plates in the same way as light or X-rays; (2) that they excit« phosphorescence in certain substances whten brought in their neighbourhood; (3) that they cause the air and other gases around them to lose the insulating power th«y nominally possess, and to become partial conductors of electricity thus leading to the rapid discharge of the electricity in any electrified object brough near to them ; and (4) that they generate heat as does coal or any other substance burning. These effects are said to be produced by rays, given off by the radio-active substances. Mr Soddy explains the nature of the rays, and the reasoning by which it has been established that what is really taking place is the disintegration or break-up of atoms of the radio-active substances. The process of disintegration has been traced through several successive stages in the case of radium. First a radium atom throws off a particb, which is an atom of helium. The remainder of the disintegrated atom of radium goes to form what is called the emanation, a gas which in the couise of a few days discharges » 6econd helium atom. The residue forms a solid deposit, which in a faw minutes pusses through three rapid changes. Then, according to the descriptions, foilow three more changes, the first of which takes some years, and the second and third about a week ea-eh. The last pfoduct of these changes is th-r> clement polonium, whi<"h Madame Curie discovered in pilohblonde before radium. Polonium is described as unstable, with an average life of 203 days, and its atom throws off an atom of 'helium, but into what the residue of its disintegrated atom is converted )» not yet known. Lead, however, in believed to be the ultimate product of this series of atomic changes. As polonium ia derived from radium so radium is derived from uranium. But by far the most startling feature of these* phenomena is ftated to bo the enormous relative amount of energy released. All the disintegrating changes are accompanied by •explosive discharges of energy. The total amount of energy evolved by radium in its course, of change is about 2,000,000 times as much as is evolved from the same weight of coal in burning. It i» declared that the energy in a ton of uranium would be sufficient to light London for a year. The energy must be stored up in the atom of uranium, and the atom must therefore be some very highly complex piece of mechanism. Scientists say it is almost impossible to believe that Tadio-active elements alone possess this store of internal energy. The question is — and his phase of the subject has been more than onco been doalt with in out topics — is whether man can ever draw for rtho purposes of life upon this wealth of atomic energy. Mr Soddy says: "Wo cannot yot. artificially accelerate or influence the rate of disintegration of an clement, and therefore the enercry in uranium, which requires a thousand million years to be evolved, is practically useless. On the other hand, to increase the natural rate, and to break down uranium or any other el?--ment artificially, is simply transmutation. If wo could accomplish the one so we could the other. These two greatproblems, at once the oldest and newest in science? are Vme. Transmutation of the elements carries with it the power to unlock the internal energy of matter, and the unlocking of th? internal atoms of energy in matter would, strangely enough, be infinitely the most important and valuable consequence of transmutation." Mr Soddy, it is stated', looks hopefully to the day when elements will he broken down and built up in the laboratory, as chemical compounds now are. "The pulse of the world would then," as ho puts it, "throb with new force, as immeasurably removed from any we at present control as they, In turn, are from tho natural resources of the human savage.'