24 Jiiographical Memoir of' Sir John Leslie. 



Mhich he was so peculiarly qualified to cultivate. One of the 

 lirst cares of his new situation'was, the extension of the appara- 

 tus required for that greatly enlarged seriesof experiments which 

 he thought necessary for the illustration of the Course. This, in- 

 deed, was an object of which, from the first to the last year of his 

 incumbency, heneverlost sight; and it is due to him to state, that 

 it was through his exertions that the means of experimental il- 

 lustration, in the Natural Philosophy Class, Avere for the first 

 time made worthy of the University. Viewing him merely as 

 rt lecturer, it must be admitted that he was not eminent. He 

 was apt to forget, or rather did not perceive, that the connect- 

 ing links between premises and conclusion, though familiar to 

 the teacher, may, to the learner, be all unknown ; that views 

 quickly reached by the acquired perceptions of the one, must 

 be opened up, step by step, to the yet imperfect vision of the 

 other ; and that it is the imperative duty of a public instructor 

 to bring down knowledge from its highest spheres, and place it 

 on a level adapted to the powers of unpractised understandings. 

 His views of the nature of science were grand and animating ; 

 and his strictures on the great discoveries which constitute the 

 epochs of its historjr, sometimes swelled into lofty strains of 

 eloquence ; but, generally, in lecturing, as in writing, he want- 

 ed that consecution of thought, and that perspicuity of expo- 

 sition, without which reasoning cannot be made intelligible, 

 nor its conclusions satisfactory. Still, the attraction of his 

 numerous experiments, the celebrity of his name, and the 

 opinion entertained of his extraordinary powers, joined with 

 o-reat simplicity and affability of manner, concurred to secure 

 him the respectful homage of his students, and to sustain the 

 glory of the University. In 1823, he published, chiefly for 

 the use of his class, a volume entitled Elements of Natural 

 Philosopluj : being the first of a Course intended to extend to 

 three, and to exhibit a comprehensive view of the principles of 

 that cono-eries of sciences which we are<.aecustomed to class un- 

 der the above term. Here, as was the case with his Mathema- 

 tical Course, his plan was not completed ; for he published no 

 part of it but the volume mentioned, which includes only Me- 

 chanics and Hydrostatics. A second edition of this volume, 

 corrected, and augmented with Notes, was published in 1829, 

 three years before his death. 



