III. THE LEAF. 57 



power of the tree, it becomes sap, properly so called, 

 which passes downwards through this cellular tissue, 

 slowly and secretly ; and then upwards, through the 

 great vessels of the tree, violently, stretching out the 

 supple twigs of it as you see a flaccid waterpipe 

 swell and move when the cock is turned to fill it. 

 And the tree becomes literally a fountain, of which 

 the springing streamlets are clothed with new-woven 

 garments of green tissue, and of which the silver 

 spray stays in the sky, — a spray, now, of leaves. 



19. That is the gist of the matter; and a very 

 wonderful gist it is, to my mind. The secret and 

 subtle descent— the violent and exulting resilience 

 of the tree's blood, — what guides it ? — what compels ? 

 The creature has no heart to beat like ours ; one 

 cannot take refuge from the mystery in a ' muscular 

 contraction.' Fountain without supply — playing by 

 its own force, for ever rising and falling all through 

 the days of Spring, spending itself at last in 

 gathered clouds of leaves, and iris of blossom. 



Very wonderful ; and it seems, for the present, 

 that we know nothing whatever about its causes ; 

 — nay, the strangeness of the reversed arterial and 

 vein motion, without a heart, does not seem to 

 strike anybody. Perhaps, however, it may interest 

 you, as I observe it does the botanists, to know 

 that the cellular tissue through which the motion 



