46 THE SCIENTIFIC PAPERS OF 



1839. The most suitable diameter of the conductor, in submarine 

 cables, under given circumstances, might be ascertained without 

 much difficulty from the simple formulae which he had given, and 

 which he had hoped would have formed a principal point in the 

 discussion. 



The, Chairman said it was now his pleasing duty to call upon the 

 meeting to join him in a cordial vote of thanks to Mr. Siemens 

 for his very elaborate and valuable paper. He had almost hoped 

 to have heard the battle of magneto-electric and battery power 

 fought over again, as he saw advocates of both systems present. 

 Professor Wheatstone was avowedly in favour of the magneto- 

 electric power, and there had been of late many important im- 

 provements in that direction. They had heard that evening one 

 extraordinary communication from Mr. Latimer Clark, which 

 came with great surprise upon all who were acquainted with the 

 normal history of electricity. This statement was, that Oersted was 

 not the first discoverer of electro-magnetism. If a priority of 

 discovery were established on behalf of any other person, it would 

 come with great surprise upon those who had been accustomed to 

 associate that discovery with the name of Oersted since the year 

 1821. The only scintilla of any prior claim to the discovery was 

 that which was vaguely put forward by Ritter, a man who was no 

 doubt very much underrated in his day. The Chairman con- 

 cluded by proposing a vote of thanks for the paper which had 

 been read. 



A vote of thanks was then passed to Mr. SIEMENS. 



