Vegetable Staticks] p 



reafon of the reciprocal proportion) that 34 

 cubick inches may pafs the item in twelve 

 hours 5 whence its velocity in the ftem will be 

 45<f inches in twelve hours, fuppofing there 

 be no circulation nor return of the fap 

 downwards. 



If there be added to 34, (which is the leaft 

 velocity) j- of it = 1 i|, this gives the greateft 

 velocity, viz. 45f - The fpaces being as 3 : 

 4, the velocities will be 4: 3 : : 45t: 34- 



But if we fuppofe the pores in the fur- 

 face of the leaves to bear the fame propor- 

 tion, as the area of the fap veffels in the 

 ftem do to the area of the ftem 5 then the 

 velocity, both in the leaves, root and ftem, 

 will be increafed in the fame proportion. 



A pretty exa& account having been ta- 

 ken, of the weight, fize, and furface of this 

 plant, and of the quantities it has imbibed 

 and perfpired, it may not be improper here, 

 to enter into a comparifon, of what is taken 

 in and perfpired by a human body, and this 

 plant. 



The weight of a well fized man is 1 60 

 pound : The weight of the Sunflower is 

 three pounds, fo their weights are to each 

 other as 160 ; 3, or as 53 :«i. 



1 The 



