980 REPORT— 1898. 



foot than the smaller gauge. I have been able to carry experiments further at the 

 Tower Bridge by observing the pressure on the surface of the bascules of the bridge 

 as evidenced by the power exerted by the actuating engines. In this case we have 

 a wind gauge of some 5,000 feet in area, and it has been shown that, while small 

 anemometers placed on the fixed parts of the bridge adjoining the bascules register 

 from 6 to 9 lbs. per square foot, the wind pressure on the bascules is only from 1 

 to 1^ lb. per square foot. 



It is difficult to imagine the amount of money which has been expended in 

 provision against wind strains of 56 lbs. per square foot on large areas in conse- 

 quence of hurried generalisation from insufficient data. I know something of 

 what this provision for wind cost at the Tower Bridge, and I do not wish to 

 mention it : but if the public had been told that the dictum of experts, arrived at 

 however hastily in 1880, was to be set aside in the construction of that bridge, all 

 confidence would have been beforehand destroyed in it, and I suppose no Com- 

 mittee of Parliament would have passed the Act. 



I have mentioned these matters, which could be added to by manj' similar 

 instances in other branches of applied science, not for the sake of reviving old con- 

 troversies or of throwing a stone at highly distinguished men, honoured in their 

 lifetime and honoured in their memory, nor for the sake of criticising more 

 modern scientists or a Government Department. Still less do I wish to question 

 the necessity and value of mathematical calculations as applied to the daily work 

 of engineering science, but I recall the circumstances for the purpose of once more 

 pointing out the extreme value of experimental research and of bespeaking 

 the utmost caution against our being tempted to lay down laws based on un- 

 ascertained data. We know the tendency there has been at all times to gene- 

 ralise and to seek refuge in formulae, and we cannot but know that it is not at 

 an end now. We ought to recognise and remember how few physical questions 

 had been exhaustively examined sixty years ago, and may I say how compara- 

 tively few have even now been fundamentally dealt with by experiment under true 

 scientific conditions ? The investigation of physical facts under all the various 

 conditions which confront an engineer requires much care, intelligence, time, 

 and last, not least, not a little money. In urging the vital necessity of 

 investigations, I am sure that I shall not be understood as decrying the 

 value of the exact analysis of mathematics, but we must be quite sure that the 

 premises are right before we set to work to reason upon them. We should, then, 

 exert all our influence against rules or calculations based merely on hypothesis, and 

 not be content with assumptions when facts can be ascertained, even if such 

 ascertainment be laborious and costly. In a word, let us follow sound in- 

 ductive science, as distinguished from generalisations ; for ' Great is truth and 

 mighty above all things.' 



In connection with this subject, I may congratulate the Association generally, 

 and this Section in particular, that there is now more hope for experimental 

 science and some endowment of research m this country than at any former time. 

 The vital necessity of further work in these directions has long been recognised 

 by men of science, and was notably urged by Professor Oliver Lodge, 

 Last year, in no small degree owing to the exertions of Sir Douglas Galton, 

 K.C.B., who presided over the British Association in 1895, and brought the 

 question very prominently forward in his inaugural address on that occasion, a 

 highly influential deputation waited on the Premier to urge that England 

 should have a Public Physical Laboratory, at which facts could be arrived at, 

 constants determined, and instruments standardised. The importance of the 

 questions which could be determined at such an institution in their influence 

 on the trade and prosperity of the country, independently of the advancement 

 •of purely scientific knowledge, cannot well be exaggerated. 



Our Government, while somewhat limiting the scope of the inquiry, appointed 

 a small Committee to examine and report on this highly important subject. It is 

 no breach of confidence to say that the Committee, after taking much evidence, 

 visiting a similar and highly successful institution on the Continent, and studying 

 the question in all its bearings, were convinced of the great public benefits which 



