BOOK II.] MOTION OF CONGREGATION. ^43 



RO\rg wheat and plants rincyarcls ; being only a definition 

 deduced from effects, and those but partial. But it is still more 

 to be blamed, because those effects, such as they are, are not a 

 pecuHar property of heat, but a mere accident (for cold, as we 

 shall afterwards show, does the same), arisinc: from the desire of 

 the homogeneous parts to unite ; the heat then assists them in 

 breaking through that sluggishness which before restrained their 

 desire. With regard to the assistance derived from the power 

 of a similar body, it is most conspicuous in the magnet when 

 armed with steel, for it excites in the steel a power of adhering 

 to steel, as a homogeneous substance, the power of the magnet 

 breaking througli the sluggishness of the steel. Witli regard to 

 the assistance of motion, it is seen in wooden arrows or points, 

 which penetrate more deeply into wood tlian if they were tipped 

 with iron, from the similarity of the substance, the swiftness of 

 the motion breaking through the sluggishness of the wood ; of 

 which two last experiments we have spoken above in the aphorism 

 on clandestine instances. p 



The confinement of the motion of lesser congregation, which 

 arises from the power of the predominant body, is shown in tlio 

 decomposition of blood and urine by cold. For as long as these 

 substances are filled with the active spirit, which regulates and 

 restrains each of their component parts, as the predominant 

 ruler of the whole, the several different parts do not collect 

 themselves separately on account of the check ; but as soon as 

 that spirit has evaporated, or has been choked by the cold, then 

 the decomposed parts unite, according to their natural desire. 

 Hence it happens, that all bodies which contain a sharp spirit (as 

 salts and the like), last without decomposition, owing to the per- 

 manent and durable power of the predominating and imperious 

 spirit. 



The confinement of the motion of lesser congregation, which 

 arises from external motion, is very evident in that agitation of 

 bodies which preserves them from putrefaction. For all putre- 

 faction depends on the congregation of the homogeneous parts, 

 whence, by degrees, there ensues a corruption of the first form 

 (as it is called), and the generation of another. For the decom- 



{)osition of the original form, which is itself the union of the 

 lomogeneous parts, precedes the putrefaction, which prepares 

 the way for the generation of another. This decomposition, if 

 not interrupted, is simple ; but if there be various obstacles, 

 putrefactions ensue, which are the rudiments of a new generation. 

 But if (to come to our present point) a frequent agitation be 

 excited by external motion, the motion towards union (which is 

 tlcUcjite and gentle, and requires to be free from all external 



^ See Aphorifim xxv. 



