

PRESIDENTIAL ADDRESSES. 545 



drew important lessons regarding "electrical 

 surgings " in an insulated bar of metal " induced 

 "by Maxwell's and Heaviside's electromagnetic 

 "waves," and many other corresponding pheno- 

 mena manifested both in ingenious and excellent 

 experiments devised by himself and in natural 

 effects of lightning. 



Of electrical surgings or waves in a short insu- 

 lated wire, and of interference between ordinary 

 and reflected waves, and positive electricity 

 appearing where negative might have been ex- 

 pected, we hear first, it seems, in Herr von 

 Bezold's " Researches on the Electric Discharge " 

 (1870), which Hertz gives as the third paper of his 

 collection, with interesting and ample recognition 

 of its importance in relation to his own work. 



In connexion with the practical development of 

 magnetic waves, you will, I am sure, be pleased if 

 I call your attention to two papers by Professor 

 G. F. Fitzgerald, which I heard myself at the 

 meeting of the British Association at Southport, 

 in 1883. One of them is entitled " On a Method 

 of Producing Electromagnetic Disturbances of 



VOL. II N N 



