II 



BELFAST 



NATURAL HISTORY AND PHILOSOPHICAL SOCIETY, 

 SESSION 1884-85. 



4tk November, 1884. 



Professor Everett in the Chair. 



John Brown, Esq., read a Paper on 



THE CONSTRUCTION AND USE OF INDUCTION 



COILS, 



Illustrated by Examples and Experiments. 





The reader exhibited a large coil of his own construction, with 

 others of various types made by Mr. John Edgar and Mr. John 

 H. Greenhill. The principles and action of coils, and the 

 advantages of the disc method of building up the secondary 

 were explained, as well as the most efficient disposition of a 

 given amount of secondary on a given magnetic cone. 



Some of the uses of the Induction Coil were illustrated by the 

 illumination of a beautiful set of Crookes's tubes lent by Dr. 

 Everett, the firing of submarine mines by the secondary cur- 

 rent, etc. 



