30 6 Mayow 



nature ; nor is it to be believed that the parts them- 

 selves resist their own nutrition. For they take na 

 active part in nutrition, but only passively receive the 

 nutriment brought to them : so that I do not believe 

 in any unfitness in the parts, which would lead to their 

 being less nourished, but only that there are obstruc- 

 tions which prevent their reception of the aliment : 

 wherefore the cause of this disease cannot be in the 

 constitution of the parts themselves ; nor are we to 

 look on the moisture as the cause of this disease, but 

 rather as its consequence. 



When, then, parts do indeed grow cold and are not 

 nourished, although saturated with quite suitable 

 blood, we must certainly conclude that something 

 besides blood alone is required for warmth and nutri- 

 tion. And whatever^ this may be, it must necessarily 

 be conveyed by some sort of vessels. The arteries 

 bring the blood, the veins carry it back ; and the 

 nerves alone remain as possible carriers of the nutri- 

 tive juice, or, at all events, spirits. And lest any 

 one should doubt that the nerves carry something 

 required for nutrition, I shall mention an experiment 

 known to every one, namely, that if the nerve serving 

 any part whatever be divided, not only does sensation 

 in that part cease, but also nutrition so that the said 

 part withers up. 



But indeed this nervous juice does not alone per- 

 form the whole function of nutrition. For besides 

 it, the blood diffused by the arteries has no small 

 share in nutrition. For it is the case that the 

 nervous juice when mixed with the blood produces 

 a certain effervescence and heat, and thus suitable 

 material is precipitated for the nourishment of the 

 parts : and so the blood in this disease, although in 

 itself laudable enough, yet lacking the necessary 



