LIFE AND DEATH. 419 



CANON XX. 



Juices of the body hard and rose id are good for long life. 



THE EXPLICATION. 



The reason is plain, seeing we showed before, that hard 

 things, and oily or roscid, are hardly dissipated ; notwith 

 standing there is difference (as we also noted in the tenth 

 operation), that juice somewhat hard is indeed less dissipa- 

 ble, but then it is withal less reparable ; therefore a conve 

 nience is interlaced with an inconvenience, and for this 

 cause no wonderful matter will be achieved by this. But 

 roscid juice will admit both operations; therefore this 

 would be principally endeavoured. 



CANON XXI. 



Whatsoever is of thin parts to penetrate, and yet hath no 

 acrimony to bite, begetteth roscid juices. 



THE EXPLICATION. 



This canon is more hard to practise than to understand. 

 For it is manifest, whatsoever penetrateth well, but yet 

 with a sting or tooth (as do all sharp and sour things), it 

 leaveth behind it, wheresoever it goeth, some mark or print 

 of dryness and cleaving, so that it hardeneth the juices, 

 and chappeth the parts ; contrarily, whatsoever things pe 

 netrate through their thinness merely, as it were by stealth, 

 and by way of insinuation without violence, they bedew 

 and water in their passage. Of which sort we have 

 recounted many in the fourth and seventh operations. 



CANON XXII. 



Assimilation is best done when all local motion is expended. 



THE EXPLICATION. 



This canon we have sufficiently explained in our dis 

 course upon the eighth operation. 



CANON XXIII. 



Alimentation from without, at least some other way than 

 by the stomach, is most profitable for long life, if it can be 

 done. 



THE EXPLICATION. 



We see that all things which are done by nutrition ask 

 a long time, but those which are done by embracing of the 

 like (as it is in infusions) require no long time. And there 

 fore alimentation from without would be of principal use ; 

 and so much the more, because the faculties of concoction 

 decay in old age ; so that if there could be some auxiliary 



