426 POPULAR LECTURES AND ADDRESSES. 



scripts, I believe, will be found to be excessively 

 interesting even now, and from something I heard 

 a few days ago from Professor Clerk Maxwell, 

 when he was here on the opening day of this 

 Conference, I learnt that much more than was 

 ever imagined is to be found in these manuscripts, 

 and particularly that in them has been found a 

 whole system of electrical measurements worked 

 out, from the measurement of electrostatic capacity. 

 The very idea of measuring electrostatic capacity 

 in a definite scientific way is, as it now turns out, 

 due to Cavendish. A great many years ago, 

 in 1846 or 1847, when the Cavendish manuscripts 

 were in the hands of Sir Wm. Snow Harris, at 

 Plymouth, I myself found one paper, out of a box 

 full of unsorted manuscripts, which startled me 

 exceedingly. It contained the description of an 

 experiment and its result, measuring the electro- 

 static capacity of an insulated circular disc. That 

 is one of the cases in which the theory founded 

 by Robinson and Coulomb as -developed in the 

 hands of mathematicians who followed, allowed 

 the result to be calculated a priori, and I found 



