SIR ERNEST RUTHERFORD.

Press, Volume LXI, Issue 18365, 24 April 1925, Page 20

SIR ERNEST RUTHERFORD.

CONTRIBUTIONS TO SCIENCE.

"The Scientific Work of Sir Ernest Rutherford" was the subject of Dr. C. C. Farr's presidential address to the Scientific Society at Canterbury College last night. Mr L. C. Stephens presided. Dr. Farr first dwelt npon the character of the great scientist, his charm, naturalness, even boyishness. Sir Ernest was not a musty student who worked till two o'clock in the morning with a wet towel round liis head, yet he had the power of detachment and intense concentration.

z Sir Ernest Rutherford took his M.A. degree at Canterbury College in 1894. He gained a Junior University Scholarship at Nelson College and a Senior Scholarship at Canterbury College, next year taking first-class honours iu mathematics and physics. He went to* England in 1895, having won an Exhibition Scholarship. While still at Canterbury College Sir Ernest succeeded in making some notable experiments in the young science of wireless telegraphy. On reaching England he joined the Cavendish Laboratory, where Sir J. J. Thomson was professor, and in 1896 he read a paper to the Royal Society of London on his researches on electromagnetic waves. The paper was followed by a much fuller one next year, and the two papers marked notable advances, the first describing'the transmission and.receiving of signals over threequarters of a mile, and the second the measuring of electrical resistance of a spark gap just after the spark had passed. Sir Ernest, the lecturer believed, was the first actually to measure its value, using a method entirely his own. Thus he helped to lay tho foundations of a new world-wide public convenience, but, when wireless became commercialised, he graeefully withdrew. Sir Ernest had next turned his attention to Rontgen or X-rays, and there did yeoman pioneer work. Owing to his work in Kontgen Bays, he naturally became interested in the newly discovered Uranium Rays. He threw himself vigorously into experimental work to elucidate the processes ;)/oing on in radioactive bodies and very soon began the publication of a series of papers which has gone on uninterruptedly till the present time. These papers showed a foresight and an insight -in his methods which have been the admiration of the scientific world. The immediate outcome of his investigations was the announcement by himself and Soddy of the now well-known disintegration theory. Previously men had been taught to consider atoms as created entities and a few years earlier than 1903 it would have seemed almost irreligious to dream,.much more so to suggest that one element could change into another. ■

Atomic Structure. The next few years were largely employed by Sir Ernest Rutherford and his , collaborators in sorting out the family history of what are now known as the Uranium series, the Thorium series; and the Actinium series, and in determining the, atomic weights of the different members of a family. Intense mathematical investigation' led him to formulate his now most famous and farreaching theory of atomie structure. The boldness of his conception deserved emphasis. He • imagined that all ! the positive electricity of the atom was concentrated in a central nucleus of only about .one million millionth of a centimeter in diameter, which is about one hundred thousandth of, the whole atomie diameter. Surrounding this in the form of planets, the negative electricity was to be found. This theory was something of a scientific shock. Scientists, however, were now certain that the atom is as he pictured it. Dr. Farr explained the wide influence of Sir Ernest Rutherford's work, enabling scientists to explain, problems connected with the spectrum. Another offshoot was the determination of what are known as atomic numbers.

; By smashing up the nitrogen atom into bits and since then, other atoms as well, and studying the bits Eutherford was enabled to gain some insight into the constitution of the nucleus, and during the last two or three years he has been pressing the advantage by all the possible methods of attack that his fertile brain can devise.

Sir Ernest Eutherford at present occupies the Cavendish Chair of Experimental Physics at Cambridge, having succeeded three most distinguished men, James Clerk Maxwell, Lord Ealeigh atfd Sir J. J. Thomson. "New Zealand people can feel justly proud of the man who to-day stands out as the greatest experimental physicist that the world has ever seen," concluded the lecturer.