KNOWLEDGE REQUIRES EFFORT. 5 



knowledge, without undergoing the labour by which it 

 has been usually gained, as it would be to expect that 

 an acorn will become an oak without passing through 

 the ordinary process of vegetation. We build up our 

 knowledge, augment our pleasure, and perfect our 

 nature, by struggling with and surmounting obstacles ; 

 and the earlier you assume this as a practical maxim, 

 the better. 



It is one thing, however, to be, if I may so speak, the 

 intellectual creator of a department of science, by inven- 

 tion, by discovery, and a due concatenation of principles 

 and propositions; and another, and happily a much 

 easier thing to learn a science so as to comprehend it 

 in all its bearings and applications. Nothing beyond 

 the ordinary powers of mind is requisite to study "suc- 

 cessfully any branch of philosophy. Facts, which are 

 the materials of science, may be recollected and classified 

 by him who has not opportunity to collect them ; ex- 

 periments may be understood by him who probably 

 could not make them ; and a logical system of scientific 

 truths, appropriately demonstrated, may be studied with 

 delight, and thoroughly comprehended, by one who is 

 altogether incompetent to write a treatise; it being, 

 in truth, this obvious difference in the scale of acquisi- 

 tion, that constitutes the main distinction between the 

 pupil and the preceptor. 



Thus much being premised, I invite your attention 

 to a rapid sketch, principally historical, in which my 

 desire is, partly to direct your researches, partly to 

 gratify curiosity, but much more, I confess, to excite 

 it, to stimulate to inquiry and exertion, by showing, in 

 a brief selection, what has been, and what may again 

 be, their noble reward. 



