1890 - 91 .] Chairmans Opening Address. 3 
worthiest successor to Sir William Thomson was our indefatigable 
General Secretary. 
But Professor Tait, with that appetite for work which does not 
know the meaning of satiety, thought that he could be of more use 
to the Society in his present office than in the more dignified 
position of your President, and thus he sacrificed that distinction, 
which might be a legitimate object of ambition to any man, for the 
general good of us all. The Bellows of the Society will not fail 
to appreciate this act of self-sacrifice on his part ; and will not for 
a moment fancy that I have less sense of the honour I now enjoy, 
because Professor Tait had not seen fit to accept of it. 
Our learned Vice-President, Lord McLaren, who in July last 
occupied this Chair at the closing meeting of the preceding Session, 
adverted to the loss the Society had sustained since the commence- 
ment of the Session, by the removal by death of ten of its Ordinary, 
and one of its Honorary, Bellows ; and he mentioned in the case of 
several of them a few of the incidents in their respective careers by 
which they had made themselves honourably known. Since that 
address was delivered eight more of our Ordinary Bellows have 
died, and I wish to be allowed now briefly to say a few words 
regarding each of them. 
Dr James Stark, who joined the Eoyal Society in 1850, was born 
in Edinburgh in 1811. He was the son of Mr John Stark, Printer, 
also a Bellow, and a zealous cultivator of Natural History. James 
Stark studied for the medical profession at the University of 
Edinburgh, and took the degree of M.D. in 1833. His Thesis on 
that occasion was on the way in which the colours of substances 
affected the absorption by them of odours to which they were exposed. 
His experiments led him to the conclusion that odours were most 
readily absorbed by dark surfaces ; and he conjectured that perhaps 
contagious emanations followed a similar law, which led him to the 
somewhat wide induction that the established dress of the physician, 
the “ customary suits of solemn black,” were the worst adapted for 
his profession. 
Dr James Stark is most to be remembered as a pioneer in Scot- 
land in the cultivation of that important and fundamental branch 
of Sanitary Science, Vital Statistics. In 1854, shortly after the 
office of the Registrar-General for Scotland was established, he 
