1897.] 



on Contact Electricity of Metals. 



523 



his experiments, proving it in that year to a Commission of the 

 French Institute (Academy of Sciences). It is quite marvellous that 

 the fundamental experiment (§1 above), simple, easy and sure as it 

 is,* is not generally shown in courses of lectures on electricity to 

 students, and has not been even mentioned or referred to in any 

 English text-book later than 1845, or at all events not in any one 



of a large number in which I have looked for it, except in the * Ele- 

 mentary Treatise on Electricity and Magnetism,' founded on Joubert's 

 *Traite Elementaire d'Electricite,' by Foster and Atkinson, 1896 

 (p. 136). The only other places in which I have seen it described 

 in the English language are Eoget's article in the 'Encyclopaedia 

 Metropolitana ' referred to above ; Tait's ' Eecent Advances in Physical 

 Science,' 1876 ; and Professor Oliver Lodge's most valuable, interest- 

 ing and useful account of all that had been done for knowledge of 

 contact electricity from its discovery by Yolta till 1884, in his Keport 



* Fully and clearly described in Eoget's article on " Galvanism, 

 • Encyclopaedia Metropolitana,' vol. iv. edition 1845, p. 210. 



in the 



