290 THE EDINBURGH PROFESSORS 



records, and that this bright period of brilliant research should 

 have become obscured by the scholasticism inherent in the 

 method of classification which he himself did so much to 

 popularise. 



In accordance with tradition, the Chair vacated by Hope 

 was filled by the election of another medical practitioner in 

 Edinburgh. Daniel Rutherford was born in Edinburgh 3rd 

 November, 1749, the son of Dr John Rutherford, who as Pro- 

 fessor was associated with Alston and others in the reformation 

 of the Edinburgh Medical School. He was distinguished both 

 as a classical scholar and as a mathematician, and after 

 graduating M.A. at the University of Edinburgh, he entered on 

 the medical curriculum, obtaining his diploma of M.D. in 1772, 

 His thesis, when applying for the degree, was " De aero fixo 

 dicto aut Mephitico," and by this he became famous through 

 the distinction he established in it between carbonic acid gas 

 and nitrogen, though he did not give nitrogen its name. The 

 exposition he gave of his precise experimental work has been 

 allowed to entitle him to be regarded as the discoverer of 

 nitrogen, although shortly before the appearance of his thesis 

 Priestley had practically, if less methodically, covered the ground. 

 After graduation, Rutherford travelled in France and Italy, 

 returning to Edinburgh in 1775 to begin the practice of Medicine, 

 becoming Fellow of the Royal College of Physicians, of which 

 he was afterwards President. 



Rutherford was a chemist, and I have not discovered in any 

 references to him expressions that would show he was at this 

 period of his life interested in plants otherwise than as objects 

 for his experiments in relation to the chemistry of the atmo- 

 sphere. In seeking for a reason to explain his selection as 

 Hope's successor in the Chair of Medicine and Botany, one may 

 suggest either the general one of recognition of his scientific 

 ability, or the more special one that in experimenting with 

 plants he had been following on the lines of work so con- 

 spicuously developed by Hope. And of course at that time 

 some general knowledge of Botany had to be the possession 

 of every successful physician. 



Like his predecessors, Rutherford had to undertake clinical 



