50 ii. 14 — ii. 16. 



excess of either heat or cold. And as the brain of man is larger 

 and more fluid than that of any other animal, it requires a 

 proportionately greater amount of protection. For the more 

 fluid a substance is, the more readily does it get excessively 

 heated or excessively chilled, while substances of an opposite 

 character are less liable to such injurious affections. 



This however is a digression, into which we have been led 

 by the close connection of hair and eyelashes ; the causes 

 to which these latter owe their existence being the real matter 

 in hand. We must therefore put off all further details 

 concerning the hair till the proper occasions arrive and then 

 return to the full consideration of the subject.'*' 



(Ch. 15.^ Both eyebrows and eyelashes exist for the pro- 

 tection of the eyes ; the former that they may shelter them, 

 like the eaves of a house, from any fluids that trickle down 

 the head ; ^ the latter to act like the palisades which are 

 sometimes placed in front of enclosures, and to keep out any 

 objects which might otherwise get in. The brows are placed 

 over the junction of two bones,^ which is the reason that in 

 old age they often become so bushy * as to require cutting. 

 The lashes are set at the terminations of small blood-vessels. 

 For the vessels come to an end where the skin itself 

 terminates ; and, in all places where these endings occur, 

 the exudation of moisture of a corporeal character necessitates 

 the growth of hairs,* unless there be some operation of nature 

 which interferes, by diverting the moisture to another purpose.^ 



(Ch. 16.) In the generality of viviparous quadrupeds, there is 

 no great variety in the forms of the organ of smell. In those 

 of them however whose jaws project forwards and taper to a 

 narrow end, so as to form what is called a snout, the nostrils 

 are placed in this projection, there being no other available plan ; 

 while, in the rest, there is a more definite demarcation between 

 nostrils and jaws. But in no animal is this part so peculiar 

 as in the elephant, where it attains an extraordinary size and 

 strength. For the elephant uses its nostril as a hand ; this being 

 the instrument with which it conveys food, fluid and solid alike, 

 to its mouth. With it, too, it tears up trees,^ coiling it round 

 their trunks. In fact it applies it generally to the purposes of 

 a hand. For the elephant has the double character of a land 

 animal, and of one that lives in swamps. Seeing then that it 

 659 a. 



