430 Lord Rayleiijh. 



been utilized for ships and the flow of liquids by Froude 

 and by Osborne Reynolds. 



He appears to have been self-taught in what he once 

 called the art of experimenting, which in the case of a 

 powerful and observant mind is perhaps the best teaching of 

 all. He began mainly on the subject of sound and vibrations, 

 in which the interpretation of apparatus is as important as 

 Its perfection ; and by aid of the ordinary musical appliances, 

 and local help such as that of the village blacksmith, he 

 managed that, the experimental side. of his subject should 

 march parallel with the mathematical theory. Perhaps it is 

 not too much to say that he discovered in this way directly, 

 from his own experience, the wonderful degree of accuracy 

 of which suitably designed experiment is capable : and when 

 later at Cambridge he undertook the formidable task of the 

 precise determination of the electrical standards, with aid 

 of the resources of a laboratory, he came fresh to the problem 

 with clear views of what could be effected and what it was 

 worth while trying to achieve, untrammelled by habit or 

 conventional forms of apparatus. The preference for simple 

 direct means maintained itself throughout all his work, and 

 constitutes one of its charms as well on the mathematical as 

 on the experimental side. His mind may be compared in 

 this regard with that of Young, whose work, in common 

 with Helmholtz, he greatly admired ; though he would 

 hardly have gone with him so far as to say that the greatest 

 triumph of experiment is to be able to do without it, by 

 force of reasoning. It was always a wonder to visitors at 

 Terling that so much refined investigation could originate in 

 •so slight an equipment of apparatus. 



He was reflective rather than precocious, and thus was 

 somewhat slow in starting off in his career of investigation, 

 but was the more fully equipped on that account. The 

 quality of judgment, of the calm unhasting probing of 

 evidence, seems to have been always highly developed. A 

 remarkable final deliverance on the possibility of direct 

 psychical interactions was pronounced only last April in a 

 Presidential Address to the Society for Psychical Research : 



