1873.] President's Address. 11 



will place this our most honourable Medal in the hands of Professor 

 Helmholtz, and assure him that we appreciate very highly the services 

 which he has rendered to various branches of science. 



A Eoyal Medal has been awarded to Professor Allman, F.E.S., for his 

 numerous zoological investigations, and more especially for his work 

 upon the Tubularian Hydroids. The subject of these labours is one 

 upon which few persons are qualified to enter ; and the Council are im- 

 pressed with the delicacy of the work and the value of the scientific 

 results. 



PROFESSOR ALLMAN, 



In the name of the Council of the Eoyal Society, I present you with 

 this Medal, in token of their appreciation of your valuable services to 

 Zoology. 



A Eoyal Medal has been awarded to Professor Henry Enfield Eoscoe, 

 F.E.S., for his various Chemical Eesearches, more especially for his in- 

 vestigations of the Chemical Action of Light, and of the Combinations 

 of Vanadium. 



PROFESSOR EOSCOE, 



I have much pleasure, as the organ of the Council of the Eoyal 

 Society, in presenting you with this Medal, in testimony of the value 

 which the Council attach to your various Chemical researches. 



And now, gentlemen, I have to make an announcement which I could 

 wish I had been able to defer for some years. I must ask you to accept 

 my resignation of the office of President. I do this with great regret, for 

 more than one reason. I scarcely need to say that I received with great 

 pride your honourable call to that office, and that I should have valued even 

 more highly a series of repetitions of the expression of your confidence. 

 It is matter of much grief to me, personally, that I feel myself com- 

 pelled to abandon this gratification ; but I am more grieved because I 

 feel that the Presidential office has not been properly sustained, and that 

 a continuance of tenure by me might permanently endanger its efficiency. 

 The primary causes of this failure are : the severity of official duties, 

 which seem to increase, while vigour to discharge them does not increase ; 

 and the distance of my residence. It has resulted from these causes 

 that I have been unable to attend Council and Committee Meetings and 

 Meetings of the Society, and Trust Meetings connected with the Presi- 

 dency, so fully as I could have wished that I have been unable to establish 

 that personal acquaintance with my colleagues which I hold to be almost 

 essential for the good conduct of a Society and that I could not hope to 

 carrv out any measure bevond the merest routine. The difficulties which 



