412 



It is now my duty to inform you, that a Cunningham Medal has 

 been awarded by the Council to Dr. Eobert Kane, for his Eesearches 

 on the Nature and Constitution of the Compounds of Ammonia, pub- 

 lished in the First Part of the Nineteenth Volume of the Transac- 

 tions of this Academy. It would, indeed, have been much more 

 satisfactory to myself, and doubtless to you also, if one of your 

 Vice-Presidents, who is himself eminent in Chemistry, had under- 

 taken the task which thus devolves upon me, of laying before you a 

 sketch of the grounds of this award ; but at least, my experience of 

 your kindness encourages me to hope, that while thus called upon 

 officially to attempt the discharge of a duty, for which I cannot 

 pretend to possess any personal fitness, or any professional prepara- 

 tion, I shall meet with all that indulgence of which I feel myself to 

 stand so much in need. 



Although, in consequence of the variety of departments of 

 thought and study which are cultivated in this Academy, and the 

 impossibility of any one mind's fully grasping all, it is likely that 

 many of its members are unacquainted with the details of chemistry, 

 yet it has become matter of even popular knowledge, that in general 

 the chemist aims to determine the constitution or composition of 

 the bodies with which we are surrounded, by discovering the natures 

 and proportions of their elements. Few need, for instance, to be 

 told that water, which was once regarded as itself a simple element, 

 and which seems to be so unlike to air, or fire, or earth, has been 

 found to result from the intimate imion of two different airs or 

 gases, known by the names of oxygen and hydrogen, of which the 

 one is also, under other circumstances, the chief supporter of com- 

 bustion, is an ingredient of the atmosphere we breathe, and is closely 

 connected with the continuance and healthful action of our own 

 vital processes, by assisting to purify the blood, and to maintain 

 the animal heat ; this same gas combining also, at other times, with 

 some metals to form rusts, with others acids, with others again 

 alkalies and earths, entering largely into the composition of marble 

 and of limestone, and, in short, insinuating itself, with a more than 

 Protean ease and variety, into almost every bodily thing around us 

 or within us ; while the other gas which contributes to compose 

 water, though endowed with quite different properties, is also ex- 



