34 LECTURE I. 



the present occasion, to excite your atten- 

 tion ; and these are highly important, on 

 account of their re-action, and the bias 

 they impart to our opinions in general, and 

 also to our conduct. 



The study of Nature has been com- 

 pared to the working of an inexhaustible 

 mine, abounding in rich materials ; but 

 which require to be assorted, refined, and 

 wrought up, ere they can be converted 

 to useful purposes. Some dig the crude 

 materials from the mine, others assort and 

 refine them ; whilst others again, construct, 

 with the wrought substances, instruments 

 of great utility in the future acquisition of 

 knowledge. Surely, I may be permitted to 

 consider opinions as the instruments of in- 

 tellect, for it both forms them and employs 

 them in its future operations ; and when also 

 they are well constructed, they illuminate 

 and render intelligible surrounding objects; 

 but when ill formed, they only obscure and 

 disfigure the face of nature. In adverting 

 then to Mr. Hunter's Museum, by thus cir- 

 cumscribing my designs, I shall not in the 



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