THE MAN WHO GOT INSIDE THE ATOM.

Otago Witness, Issue 3511, 28 June 1921, Page 52

THE MAN WHO GOT INSIDE THE ATOM.

Tiic low-spirited patriot who wonders if we are a decaying race ought, to take a dose of science occasionally. We are, in many respects, not the most brilliant generation that England has seen. We have no Byron, no Shelley, no Fox and Pitt, no Nelson and Wellington. But we have a body of scientific men, who in sheer intellectual power and gieat achievements, keep our repute for mental vigour as bright as ever. Take, for instance, the masters of what is called, in the narrower sense, physical science. What other country could show a constellation to outshine the group of physicists and chemists which has brought honour to England in recent years—Lord Kelvin and Baron Rayleigh, Sir James Dewar and Kir J. J. Thomson, Sir A. Rucker and Sir E. Rutherford, Professor Soddy, and Sir \V. Crookes and Sir O. Lodge ? —Professor at Twenty-seven. — When Sir Ernest Rutherford and Sir Jose-ph Thomson appeared together at the BritLii Association meeting at Winnipeg in 1909, the American scientific press wondered that one con..try could own two such masters of their science. It is difficult, in fact, to choose between half-a-dozen of these men, but perhaps the fine figure of Sir J. J. Thomson will be best representative of this branch of British alienee. In the year 1884 it was necessary to appoint a Cavendish Professor of Experimental Physics at Cambridge University. The two men who had previously occupied the chair were intellectual giants—James Clerk Maxwell and Lord Rayleigh. Who would be third ? Sleepy old dons in that ancient seat of learning were astounded when they heard that a young man of to enty-seven, Joseph John Thomson, had been appointed. Is Cambridge so poor, they asked, that it turns to “boys’’? To-day, perhaps, Cambridge has no prouder ornament than the man on whom the scientific world has showered its honours so thickly. —A Manchester Man.— Thomson was born in 1856. and be was born in the Manchester district. He received his first lessons in physics at Owen's College, under that great teacher and master, Balfour Stewart. We will not say too much about “the sturdy Northerner,’’ but, in point of fact, Thomson’s conspicuous figure is quiet strength. When he stands erect, giving a lecture, the lower jaw, in spite of a heavy moustache which droops carelessly over the mouth, is very eloquent. His lectures and writings have the same plain strength. There is no introduction, no embroidery, no humour. Once he announced a lecture at the Royal Institution on “The Dynamics of a Golfball.’’ If there were any in the audience who expected that now, at least, a little humour would be dropped by the way, they were very much disappointed. Thomson began, quite seriously: There are so many dvna-mical problems connected with golf that a discussion of the whole of them would occupy far more time than is at my disposal this evening. A stranger to the game would have gathered before the hour was out that fjolf was a scientific experiment conducted in open-air laboratories in various parts of the kingdom. From Owen’s College Thomson had gone to Cambridge, where ho graduated with distinction. He continued to study in the Cavendish Laboratory, and as early a-s 1881 he took the Adams prize by a brilliant essay on physics. Three years later he became Cavendish Professor and a Fellow of the Royal Society. Then followed fourteen years of hard, plodding work, chiefly on electricity and magnetism, over which we will not linger. It was when radium was discovered in 1898 thatThomson’s great opportunity came. —Tnside the Atom.— The general public has merely a vague idea that a clever Polish-French ladv was lucky enough to drop across radium in 1898. The fact is, of course, that Professor Curie and his wife were systematically following out the work of their predecessors. For half a century physicists had been on the track of some deep secret _ of Nature of which they caught occassional glimpses. But the difficulties were tremendous. Let us put it in this wav. Take the dot over the letter “i” as it is printed on this page. We know—we know before 1898— that several million atoms of matter could be accommodated in a single lino, shoulder to shoulder, so to speak, across the breadth of that tinv spot- of ink ! What the physicists and chemists were trying to do was to get inside one of these extraordinary minute atoms and see what it was made of. Sir J. J. Thomson was the first to do so. •Weighed and Measured.— The discovery did not depend so exclusively on radium as people imagine. Long before 1898 .Sir XV. Crookes had. though no one knew it, got, the same phenomena bv discharging electricity through little tubes of rare gas. Thomson was following this up. and the new discovery of radium gave the due. These tiny atoms of matter were breaking m> into particles which were far more minute. flow could anybody even make a. mental picture of such inconceivable -mall things? Sir J. ,T. 7 bom son 1 ■ - * merelv - 1 n mental picture of them. i tq made tlu-m register themselves on photographs. Tfe weighed them, measured them, ascertained their speed. end gave the world a wonderful suggestion of how they lived within the tinv dimension'- of an atc-m. He directed thin streams of them on to a target which lit. up as each nart-icle struck it. He made them trace luminous paths through art! fioial fogs, so that they could he photographed. TTe found and proved that the smallest, of these particles—"corpuscles,” ha called them, though they are now known aa “electrons’’—were so minute

that to put it in his own recent words, “their linear dimensions are only about one-hundred-thousandth part of those of atoms” ; and it would take hundreds of millions of atoms in a continuous line to stretch across the face of a penny. —Energy Beyond Dreams. — Very interesting', you may say, but does it out any ice? You may remember, on reflection, that this question was asked, rather disdainfully, when scientific men made the researches which led to the utilisation of gas, steam, or electricity. In this case there is an even greatei possibility. These electrons are shot out of the atoms of matter at a speed which may reach, in good conditions, 160,000 miles a second. Here is locked un in the atoms of all kinds of matter energy beyond all our dreams. The energy contained in a farthing is equal to 80,COO,0(Rj horse-power. There is more, energy in the atoms of a square foot of coal than we shall tret in the ordinary way out of all the coal in Britain. —Can We Tap It.— Whether or no' we shall succeed in tapping this energy remains to be seen. In any cane we have made a prodigious stride in the understanding of Nature, which is the first- condition of our being able to develop its splendid resources. The atoms of all kinds of matter are little worlds of these infinitesimal electrons —magazines of extraordinary energy. Every arc lamp is sho-oting them out at a prodigious speed. The sun is pouring them out in floods. They are “atoms of electricity” ; and it may be said in a sense that the whole material world is made up of electricity. It is something, at least, to have mastered the nature of that wonderful force. Sir J. J. Thomson’s first suggestion of the way in which these electrons are held together in the atom may give place to others, but the substance of liis brilliant work remains. -—Many Honours.—Thomson has trained a splendid body of men at Cambridge to carry on the work. As a teacher he had a way of his own. He let the men work, and rarely interfered. Only at tea time he gathered the whole twenty or thirty of them in his room daily, and the talk was varied and vociferous. -Sir J. J. Thomson’s views on life are not anaemic. His students shared his enthusiasm. As he says somewhere, the new discoveries had an effect on the scientific world something like the wine of the Renaissance in the fifteenth century. Already some of his pupils have made high reputations. But Thomson himself is no old man. He is not yet sixtylive. Honorary degrees from nine universities, Fellowships in a dozen of the greatest scientific bodies in the world, the Nobel Prize, the Order of Merit, gold medals—he has nearly everything. With the customary quietness of a master of science he works on, to the honour of Britain and the profit of humanity.—John o’ London’s Weekly.