ii4 POPULAR LECTURES AND ADDRESSES. 



is the most practical, has very great interest 

 attached to it, as being the way of doing the 

 thing in one process that is the method of 

 electrical oscillations. 1 I should certainly like to 

 see how a person who has lost his standards, 

 after having recovered his centimetre (which he 

 certainly would do by the wave-length of light), 

 would succeed in recovering his unit of time by 

 the following method. Take a condenser a very 

 large Leyden jar ; electrify it, and connect the 

 two poles through a conductor, arranged to have 

 as large an electro-magnetic quasi inertia, 2 electro- 

 magnetic self-induction as possible. The method 

 is given in Clerk Maxwell's Electricity and Mag- 



1 See my Papers, on "Transient Electric Currents," Glasgow 

 Philosophical Society Proceedings, vol. III., Jan. 1853, and 

 Philosophical Magazine, June, 1853 ; now constituting Article LXII. 

 of my Reprint of " Mathematical and Physical Papers," vol. I., 1882. 



2 See on this subject my Paper " On the Mechanical Value of 

 Distributions of Electricity, Magnetism, and Galvanism," read 

 before the Glasgow Philosophical Society, January 1853, and pub- 

 lished in their Proceedings (vol. iii.) for that date ; also ariicle 

 "Dynamical Relations of Magnetism," Nichol's "Cyclopaedia of 

 the Physical Sciences," 2nd edition, 1860. These two Papers, wilh 

 additions of date July 1882, now constitute Article LXI. of my 

 Reprint of " Mathematical and Physical Papers," vol. I., 1882. 



