REMINISCENCES OF LORD KELVIN

Evening Star, Issue 18714, 16 August 1924, Page 4

REMINISCENCES OF LORD KELVIN

[By An Old Student.] [Written for the 1 Evening Star.’) Recent newspapers from the Home Country contain copious references to the centenary of the birth of William Thomson, Lord Kelvin, which too place in Belfast on the 26th of June, 1824. The occasion was specially honored in the cit\ of Glasgow, with which he was practically all his life associated. For his parents came to reside there when he was six years old; at the abnormally early age of ten he was enrolled as a student in Glasgow University; for fifty-three years he occupied thd Chair of Natural Philosophy, and finally was the much -beloved Chancellor of that ancient scat of learning. Lord Kelvin was first and foremost a mathematician. On the basis of an extraordinary mathematical genius, he raised i an edifice of scientific attainment which has probably never been equalled. Master :cf tha whole realm of physics, he had a 1 peculiar gift in the application of scientific principles to practical problems: so ! that, though he will be known to posterity for such achievements as the statement ' of the law of the dissipation of energy, j he will he known to a much wider circle os the man who laid the first Atlantic cable, and invented the modern compass. The object-of this paper is not to review his life’s work, but to set down one or two reminiscences warmly cherished by one who was privileged to be a student in his classes in the eighties of last century. Natural philosophy met at 9 o’clock in the morning in a class room, large but often dingy, in the west front of the University. The professor lectured twice a week, the other three days being given over to an assistant. Lord Kelvin, alas! was no great teacher. Ho had not the faculty of making difficult things easy to ignorant minds. You could see him trying to do so. Ho would begin simply enough; hut before many minutes were past "be was taking leaps and bounds m bis exposition which very few of his students were able to follow. He was unconscious of the intermediate steps which he was jumping over, and unaware that wo were unconscious of them, too. Yet the discipline of the class was excellent. Men sat and wondered at him. but never thought of interrupting. He was too greatly revered and loved for his gentleness, his transparent simplicity, his deeprooted modesty. There were moments, too, when a thrill went through the class; as one morning, when he had been lecturing on optics, fie described and discussed the mechanism of the eye, then turning from his models and diagrams, lenses and prisms, he faced the rows of benches, and asked in a whisper of genuine awe: “ And who will say there is no mark of a Designer there? ”

He was never at homo in experiments — that is to say, in the simple experiments of the class room. When he got going he would spend too much time on them, amd as often as not they miscarried. The same humorous situations, the same accidents, happened year after year; and the class, inheritors of tradition, watched foi them. Was it how to calculate the velocity , of a bullet issuing from a rifJo by firing it ' into the hob of a great pendulum ? We knew that meant the little man hobbling down from .his rostrum—he was very lame —with the loaded rife, obviously an unfamiliar object of anxious care, taking his place in the front row of students, aiming his piece at the bob an inch or two from the muzzle, and discharging it, amid rounds ol applause, hobbling back to his place again with manifest relief that the dangerous business was well over. Or was it the great glass tank filled with water into which he projected a beam of light to illustrate reflection and refraction? He would surely want the tank tilted up and shaken to make ripples on the surface, forgetting that it was far too heavy for any man to move. Ho called to Malcolm, his factotum—Malcolm Somebody or Somebody Malcolm, nobody ever knew—and Malcolm essayed the task in vain. He rushed to it himself, and heaved with all his strength, while the class cheered, but in vain. It never occurred to him to arrange a lever for the purpose. But the climax of catastrophes came on the morning when he discussed capillary attraction and surface teusion. 1A drop of water, he fold us, depending from the end of a lead pencil would take cither of two forms : it might be hemispherical Or it might be elongated and somewhat pear-shaped. Of course, a drop on the end of a pencil was too small to exhibit to a class. So he had arranged something on a larger scale. Here was a tub suspended from the rafters, the bottom knocked out of it, and a diaphragm of rubber substituted. He poured water into it through a hose. The rubber stretched. A mammoth drop appeared depending from the tube, the rubber supplying the surface tension. Was it spherical ? A touch and it would take the pearshaped form. Pear-shaped ? A gentle pressure would cause it to become spherical. Pear-shaped, spherical. _ Spherical, pear-shaped. So interested did ho become in the mutations that he continued touching and pressing till the inevitable happened. The skin burst, and some gallons of cold water splashed down upon the asonished and chagrined professor. It was a joke with his students that Lord Kelvin could nob do a simple arithmetic sum. No doubt he could if he had to. But the fact remains that we have seen him stand puzzled before a very simple calculation, and then turn to an assistant with the request that he would ;work it out for him. His mind found difficulty in condescending to such schoolboy work, especially in the excitement of lecturing. On the other hand, he would cover a blackboard with the most forbidding array ol mathematical forraulre, look at it a moment, with his head a little one side, and say: “Approximately—so and so.” His “ approximately ” would prove accurate to three or four places of decimals.

It was his custom ‘ to invite his students —or some of them at least—in batches to supper at his house. We well remember the night we spent there. What we ate and drank wo know not, but the impression remains of a generous table. The entertainment of the evening was a magic lantern show. Tho Forth Bridge was building at the time, and the slides illustrated that wonderful piece of engineering, while our host lectured away for hours on all its amazing ingenuity. It was late when we scrambled for our coats in the halt He bade us good-night, but some confusion of head, gear reminded him of a story, which he told us. Whether ho treasured the story for its humor or kb an illustration of the scientific analysis a peculiarity of dialect we were not *nre. Lord Kelvin’s sense of humor was {aot highly developed. The yarn was about a Paisley man who was on board a steamer when the boiler burst. There was a great commotion; many were injured, and some few were killed. But, amid all the stir and din, the Paisley man was heard shouting, as ho ran to and Jro: “ Has anybody seen ma hatt? ” Paisley people, as Lord Kelvin pointed out to us, do not detach the tongue from the teeth when they have struck a sharp dental at the end of a word like “ hat.” Lord Kelvin’s researches and conclusions involved him of necessity in many controversies. His characteristic in all discussion was his extreme courtesy. He was endlessly patient with adversaries, and never wrote a sentence with intent to wound. It is recorded of him that when a younger colleague wrote to him asking whether he ought to reply to a wellknown man of science who had criticised some work which he and his chief had done together, Lord Kelvin telegraphed: “ By all means answer, but don’t hit too hard. Remember, he is four times your , age.” Huxley, after a long controversy £be age of the .earth, said of him

that > “ gentler knight never broke a lance." True humility is over the parent of gentleness. And Lord Kelvin was a devout apd humble man. With all his vast range of knowledge he was always conscious of the limits thereof, and even spoke in all seriousness of his life-long quest ns failure. It was in his speech at the banquet tendered to him on the completion of fifty years' tenure of his chair that he said": “ One word characterises the most strenuous of the efforts for the advancement of science that I have made through fifty-five years: that word is Failure. I know no more of electric and magnetic force, or of the relations between other, electricity, and ponderable matter, or of chemical affinity, than I knew and tried to teach my students of natural philosophy in my first session as professor.”