230 NOVUM ORGAKUM 



medium, such as air; and that there should be borne through 

 the air, at the same time, so many images of visible objects, 

 so many impulses of articulation, so many different per 

 fumes, as of the violet, rose, etc., besides cold and heat, 

 and magnetic attractions; all of them, I say, at once, with 

 out any impediment from each other, as if each had its paths 

 and peculiar passage set apart for it, without infringing 

 against or meeting each other. 



To these lancing instances, however, we are wont, not 

 without some advantage, to add those which we call the 

 limits of such instances. Thus, in the cases we have 

 pointed out, one action does not disturb or impede an 

 other of a different nature, yet those of a similar nature 

 subdue and extinguish each other; as the light of the sun 

 does that of the candle, the sound of a cannon that of the 

 voice, a strong perfume a more delicate one, a powerful heat 

 a more gentle one, a plate of iron between the magnet and 

 other iron the effect of the magnet. But the proper place 

 for mentioning these will be also among the supports- of 

 induction. 



XLIV. We have now spoken of the instances which 

 assist the senses, and which are principally of service as 

 regards information; for information begins from the senses. 

 But our whole labor terminates in practice, and as the 

 former is the beginning, so is the latter the end of our 

 subject. The following instances, therefore, will be those 

 which are chiefly useful in practice. They are compre 

 hended in two classes, and are seven in number. We call 

 them all by the general name of practical instances. Now 

 there are two defects in practice, and as many divisions of 

 important instances. Practice is either deceptive or too 

 laborious. It is generally deceptive (especially after a dili- 



