98 ADVANCEMENT OF LEARNING 



sought in mean relations and small portions. The mag 

 netic virtue of iron was not first discovered in bars, but 

 in needles. 



But in my judgment the use of mechanical history is 

 of all others, the most fundamental toward such a natural 

 philosophy as shall not vanish in the fume of subtile, sub 

 lime, or pleasing speculations; but be operative to the en 

 dowment and benefit of human life; as not only suggesting, 

 for the present, many ingenious practices in all trades, by 

 connecting and transferring the observations of one art to 

 the uses of another, when the experience of several arts 

 shall fall under the consideration of one man; but as giv 

 ing a more true and real illumination with regard to causes 

 and axioms, than has hitherto appeared. For as a man s 

 temper is never well known until he is crossed; in like 

 manner the turns and changes of nature cannot appear so 

 fully, when she is left at her liberty, as in the trials and 

 tortures of art. 



We add, that the body of this experimental history 

 should not only be formed from the mechanic arts, but 

 also from the operative and effective part of the liberal 

 sciences, together with numerous practices, n.ot hitherto 

 brought into arts; so that nothing may be omitted which 

 has a tendency to inform the understanding. 6 



5 And therefore the history of sophistications, or adulterations and frauds 

 practiced in arts and trades, ought to be inserted, which the learned Morhof 

 adds as a fourth part of this experimental history, though it may seem sufficiently 

 Included under the history of arts, as being the secret part essential to every 

 art, and properly called the mystery or craft thereof. Of these impositions, a 

 large number may be readily collected, and serve not only to quicken the under 

 standing and enrich experimental history, but also to contribute to perfect the 

 science of economical prudence. For contraries illustrate each other, and to 

 know the sinister practices of an art gives light to the art itself, as well as puts 

 men upon their guard against being deceived. See Morhof s &quot;Polyhist.&quot; torn, 

 ii. p. 128. Shaw. 



