PROCEEDINGS 



OF THE 



GEOLOGICAL & POLYTECHNIC SOCIETY 



AT THE THIRTY-FIFTH MEETING, HELD IN THE TOWN HALL, 

 PONTEFRACT, ON THURSDAY, SEPTEMBER 23rD, 1847. 



The Right Hon. Earl Fitzwilliam, F.R.S., the 

 President of the Society, took the Chair, and called upon 

 W. Sykes Ward, Esq. to read the first Paper. 



ON a new galvanometer, and on some of the phe- 

 nomena OF VOLTAIC CURRENTS. BY WILLIAM SYKES 

 ward, ESQ., LEEDS. 



In voltaic electricity, apparatus which should accurately 

 indicate the dynamic effect of a current has long been a 

 desideratum. The instruments hitherto used are objection- 

 able for some one of the following reasons : — being either 

 very delicate and expensive in their construction, requiring 

 tedious manipulation, or giving results which at best are only 

 approximative, or which require considerable powers of cal- 

 culation to reduce their indications to a real value. I believe 

 that the little instrument I have the pleasure of introducing 

 is not liable to any of these objections, that it will assist the 

 mathematician in obtaining the data he may require, and 

 enable the experimentalist easily to record the power which 

 he employs. Prior to describing my galvanometer, it may 

 not be uninteresting to you, particularly to those who are not 



