PLYMOUTH INSTITUTION. 167 



metals by tinning, is due to the improved contact, occasioned by 

 the soft and clean metallic substance thus produced. 



The discussion turned principally on the question of the identity 

 of electricity and heat ; it was finally agreed that their relations to 

 each other might be considered as similar to those existing between 

 ice and water, or between water and steam. 



October 17th. — ^The Rev. B. St. John delivered a lecture on 

 Rhetoric (the first of a series of nine) ; the discourse consisted of 

 two sections, in one of which was given an outline of the origin and 

 progress of rhetoric from its commencement as a science to the ex- 

 tinction of eloquence in ancient times, the lecturer tracing its birth 

 in the first formation of a civil society to its final perfection under 

 free and enlightened governments, and showing the influence of free 

 institutions, combined with national character and manners, on its 

 successful cultivation. The greatest orators of antiquity were 

 noticed at some length, and the excellencies of the best writers were 

 skilfully pointed out. 



The second section treated of the nature, business, end and sub- 

 ject matter of rhetoric. 



While noticing the orators of antiquity, the lecturer portrayed the 

 characteristics of Demosthenes and -Sischines in a novel and striking 

 manner: he observed — "Many comparisons have been drawn be- 

 tween these celebrated rivals by enumerating their several excellen- 

 cies, but few have succeeded for want of an image in art or nature 

 to convey an adequate idea of their merits. Thus to estimate the 

 merits of these rival orators we must place before us the statues of 

 the gladiators ; one fierce and impassioned, advancing with impetu- 

 ous stride to inflict the mortal wound on his antagonist, the other 

 fallen and reeking in the blood of a long and desperate encounter. 

 In one the sword and uplifted arm are the force and nervous ex- 

 pression of Demosthenes ; in the other, the fine frame and pros- 

 trate figure are the stately periods and verbal splendour of ^schines, 

 demolished by the might of his opponent. In one are the features 

 of a hero, who, undaunted by the deafening yells of the amphithea- 

 tre, is ready to suffer pain for glory, or to rush on to death for victory." 



In the course of the paper an elaborate vindication of Aristotle 

 was entered into, proving most clearly that, though that philosopher 

 invented syllogisms, he nevertheless used the inductive mode of 

 reasoning as well as Bacon, which was evident from his writings. 



The technical part of the lecture was lucidly developed and illus- 

 trated by two synopses of the Aristotelian logic. 



