PRESIDENTIAL ADDRESS MACKAY x 



no less value. Mr. Fletcher was much more, however, than a mere 

 geological specialist; he was an accomplished linguist, and a man of 

 wide culture and broad interests. But no sketch of him would be 

 adequate which did not above all recall characteristics of the heart 

 as well as of the head, the lovable personality, the nobility of 

 character, which will make his name long cherished in the wide 

 circle of his friends in Nova Scotia. In Mr. Fletcher's death 

 Canada loses one of its most eminent scientific men and most 

 devoted public servants. 



Work of the Institute. 



The work of the Institute for the past year has not Deen 

 characterized by any unusual features. Eleven papers were com- 

 municated. Of these four were geological, two botanical, and two 

 chemical, and of the remainder one dealt with celestial mechanics, 

 one with mineralogy, and one with the examination of cement. 



Having now submitted some report upon our doings for the 

 past year, I hope I shall be pardoned if, following the practice in 

 many scientific societies, I devote the remainder of the time given 

 me this evening to a brief discussion of a scientific topic. 



The Atomic Theory. 



The last two decades have been as rich in epoch-making work, 

 at least in the departments of physics and chemistry, as the cor- 

 responding decades a century ago which saw the formulation of 

 the laws of definite and multiple proportions and the birth of the 

 atomic theory And some of the most notable discoveries of these 

 two decades have been of such a character as to raise doubt in some 

 minds as to whether Dalton's theory is any longer tenable. On 

 the one hand the investigation of the nature of radiant matter 

 seems to show the existence of bodies a thousand times more 

 minute than the smallest of Dalton's atoms, while on the other 

 hand among many new kinds of matter discovered some have 

 revealed properties of so revolutionary and .anarchistic a character 

 as seemingly to threaten the stability of the whole chemical edifice, 

 hitherto thought to be securely founded on its century-old atomic 

 foundations. The statement is frequently heard that these dis- 



