448 POPULAR LECTURES AND ADDRESSES. 



has been issued. I really do not know, consider- 

 ing that the British Association report on electro- 

 meters has been republished in connection with 

 the whole series of their Reports on Electrical 

 Standards, 1 that I need go into detail with respect 

 to any of these instruments. This is the very 

 first portable electrometer, and I will tell you 

 how it came into existence. I had one that I 

 was very proud of, I am ashamed to say, in these 

 days. I was proud of its smallness, and how 

 easily it could be carried up to the top of Goatfell 

 and back ; there was one before that, the highest 

 character of which was, that it was not heavier 

 than a rifle. That was in the days of what Lord 

 Palmerston called the " rifle fever," and I was 

 touched a little with it at the time, being a 

 rifle volunteer. I found that my electrometer 

 weighed a pound less than my weapon. It only 

 weighed thirteen Ibs., and the rifle weighed fourteen 

 Ibs. I had that at Aberdeen, but it is not now 

 to be found, although it has been searched for, 

 or it would have been exhibited. Part of it 

 1 E. and F. N. Spon, London, 1873. 



