173 



excite attention to the practicability of an electric telegraph than 

 anything that had been done previously. 



In 1846 Professor Weber published a memoir on "The Measures 

 of Electro-dynamic Forces " (" Electrodynamische Maasbestimmun- 

 gen "), a work not less remarkable for the original mathematical than 

 for the experimental researches embodied in it. A high authority 

 has pronounced this to be " one of the most important works both 

 with regard to mathematical theory, and the practical application 

 of it, that has been published in this department of science since the 

 researches of Ampere ; " and the same authority has added, " His 

 transformation of Ampere's law of electric action, so as to exhibit 

 the analyses of the plus and minus elements in each stream, and 

 his deduction thence of the law of statical from that of dynamical 

 action, seems to me, both as a specimen of mathematical analysis 

 and of physical philosophy, exceedingly beautiful." 



More recently Professor Weber has produced two additional 

 memoirs on the same subject, one of which contains a mathematical 

 and experimental investigation of the phenomena of dia-magnetism 

 discovered by Faraday. 



PROFESSOR MILLER, 



As I have not the opportunity of presenting it to him in his own 

 person, I request of you, as Foreign Secretary, to cause the Copley 

 Medal which I now place in your hands to be conveyed to Professor 

 Weber, with a request that he will be pleased to accept it as the 

 indication of the very high estimation in which his scientific labours 

 are held by the Royal Society of London. 



One of the Royal Medals has been awarded to Arthur Cayley, 

 Esq., F.R.S., for his Mathematical Papers published in the 

 Philosophical Transactions, and in various English and Foreign 

 Journals. 



From the first institution of the Royal Society a large proportion 

 of the papers communicated to them have related to Pure Mathe- 

 matics ; and none have contributed more than these to maintain 

 the credit of the Philosophical Transactions. Among writers of the 

 present time, no one has been a more earnest or more successful 

 labourer in this department of science than Mr. Cayley. His nume- 

 rous papers on these subjects bear testimony to his unwearied indus- 



