404 Messrs. Wilson and Makower on the Rate of 



Conclusion, 



In the report of a recent Educational Conference, I noticed 

 that whilst differences arose on all other points, there was 

 absolute unanimity regarding the excellence of Euclid I.-III. 

 Now Euclid is, above all, an experimental science— the ex- 

 periment is first performed, then analysed to confirm its 

 accuracy — and the vitality of Euclid is, beyond doubt, due 

 to this pre-eminently rational treatment. 



This plan is the one I have tried to follow — with what 

 success you must yourselves decide. In more competent 

 hands it might, I am certain, be improved and extended to 

 other problems, with great benefit to all concerned. The 

 larger part of mathematics has arisen in the consideration of 

 practical questions ; and by divorcing the reasoning from its 

 original significance, we rob it both of its visible explanation, 

 its interest, and its application. The earlier portions of 

 arithmetic, algebra, trigonometry, &c. are clearly experi- 

 mental, and describe, in symbols, the results of definite opera- 

 tions which any boy can readily understand. As we advance, 

 however, the real meaning gradually becomes obscured, till 

 we are finally left with little more than a notation, intelli- 

 gible only to those possessing special aptitude. 



When the extensive and growing equipment of our labo- 

 ratories and technical schools is contrasted with the solitary 

 blackboard, it must surely be admitted that the disparity is 

 excessive. If we will but show diagrams, models, and actual 

 measurements — alluding constantly to the practical applica- 

 tions of the matter in hand, and pointing out its real utility 

 — we shall by such means do much to awaken interest, 

 stimulate intelligence, and discountenance the idea that this 

 oldest, and most important, of all the sciences is merely a 

 collection of tricks with symbols, culminating in a calf -bound 

 volume, neatly embossed with the school arms. 



XXXVI. Note on the Rate of Decay of the Active Deposit from 

 Radium. By W. Wilson and W. Makower *. 



IN some experiments in which the ionization produced by 

 . the a rays from radium C was balanced against that 

 produced by the more penetrating (3 and y rays, it was found 

 that after a short time these two ionizations were no longer 

 exactly equal, however carefully they had at first been 

 adjusted to equality. A similar effect has been noticed by 



* Communicated by the Physical Society : read May 24,, 1907. 



