The Earl of Pembroke to the Abbess of Wilton.

"Go spin, you jade! go spin!"

MAGNETISM, LIGHT, AND MOLECULAR SPINNING TOPS.

Page 122.

THE ROMANCE OF SCIENCE.

SPINNING TOPS.

THE "OPERATIVES' LECTURE"
OF THE BRITISH ASSOCIATION MEETING AT LEEDS,
6th SEPTEMBER, 1890.

BY

PROFESSOR JOHN PERRY,
M.E., D.Sc, LL.D., F.R.S.

With Numerous Illustrations.

REPRINT OF NEW AND REVISED EDITION,

With an Illustrated Appendix on the Use of Gyrostats.

LONDON
SOCIETY FOR PROMOTING CHRISTIAN KNOWLEDGE,
Northumberland Avenue, W.C.; 43, Queen Victoria Street, E.C.
Brighton: 129, North Street.
N e w   Y o r k: E.   S.   G O R H A M.

1910

PUBLISHED UNDER THE DIRECTION OF THE GENERAL LITERATURE COMMITTEE

[Date of last impression, April 1908]

This Report of an Experimental Lecture
WAS INSCRIBED TO
THE LATE
LORD KELVIN,
BY HIS AFFECTIONATE PUPIL, THE LECTURER, WHO
HEREBY TOOK A CONVENIENT METHOD OF
ACKNOWLEDGING THE REAL AUTHOR OF
WHATEVER IS WORTH PUBLICATION
IN THE FOLLOWING
PAGES.

PREFACE.

This is not the lecture as it was delivered. Instead of two pages of letterpress and a woodcut, the reader may imagine that for half a minute the lecturer played with a spinning top or gyrostat, and occasionally ejaculated words of warning, admonition, and explanation towards his audience. A verbatim report would make rather uninteresting reading, and I have taken the liberty of trying, by greater fullness of explanation, to make up to the reader for his not having seen the moving apparatus. It has also been necessary in a treatise intended for general readers to simplify the reasoning, the lecture having been delivered to persons whose life experiences peculiarly fitted them for understanding scientific things. An "argument" has been added at the end to make the steps of the reasoning clearer.

SPINNING TOPS.

————

At a Leeds Board School last week, the master said to his class, "There is to be a meeting of the British Association in Leeds. What is it all about? Who are the members of the British Association? What do they do?" There was a long pause. At length it was broken by an intelligent shy boy: "Please, sir, I know—they spin tops!"^[1]

Now I am sorry to say that this answer was wrong. The members of the British Association and the Operatives of Leeds have neglected top-spinning since they were ten years of age. If more attention were paid to the intelligent examination of the behaviour of tops, there would be greater advances in mechanical engineering and a great many industries. There would be a better general knowledge of astronomy. Geologists would not make mistakes by millions of years, and our knowledge of Light, and Radiant Heat, and other

Electro-magnetic Phenomena would extend much more rapidly than it does.

I shall try to show you towards the end of the lecture that the fact of our earth's being a spinning body is one which would make itself known to us even if we lived in subterranean regions like the coming race of an ingenious novelist.^[2] It is the greatest and most persistent cause of many of the phenomena which occur around us and beneath us, and it is probable that even Terrestrial Magnetism is almost altogether due to it. Indeed there is only one possible explanation of the Vril-ya ignorance about the earth's rotation. Their knowledge of mechanics and dynamics was immense; no member attending the meeting of the British Association can approach them in their knowledge of, I will not say, Vril, but even of quite vulgar electricity and magnetism; and yet this great race which expresses so strongly its contempt for Anglo-Saxon Koom-Poshery was actually ignorant of the fact that it had existed for untold generations inside an object that spins about an axis.

Can we imagine for one instant that the children of that race had never spun a top or trundled a hoop, and so had had no chance of being led to the greatest study of nature? No; the only possible explanation lies in the great novelist's never

having done these things himself. He had probably as a child a contempt for the study of nature, he was a baby Pelham, and as a man he was condemned to remain in ignorance even of the powers of the new race that he had created.

The Vril-ya ignorance of the behaviour of spinning bodies existing as it does side by side with their deep knowledge of magnetism, becomes even more remarkable when it comes home to us that the phenomena of magnetism and of light are certainly closely connected with the behaviour of spinning bodies, and indeed that a familiar knowledge of the behaviour of such bodies is absolutely necessary for a proper comprehension of most of the phenomena occurring in nature. The instinctive craving to investigate these phenomena seems to manifest itself soon after we are able to talk, and who knows how much of the intellectual inferiority of woman is due to her neglect of the study of spinning tops; but alas, even for boys in the pursuit of top-spinning, the youthful mind and muscle are left with no other guidance than that which is supplied by the experience of young and not very scientific companions. I remember distinctly that there were many puzzling problems presented to me every day. There were tops which nobody seemed able to spin, and there were others, well

prized objects, often studied in their behaviour and coveted as supremely valuable, that behaved well under the most unscientific treatment. And yet nobody, even the makers, seemed to know why one behaved badly and the other well.

I do not disguise from myself the fact that it is rather a difficult task to talk of spinning tops