





II 



8 



Vegetable Stattcks. 



was much fap loft, the fap would fubfide i n 

 the firft tube ; but they would not afterwards 

 have their fap in Equilibrio ; i. e. the fiu-facc 

 of the fap in each was at very unequal heights; 

 the reafon of which is, becaufe of the diffi- 

 culty with which the fap paffes thro' the 

 almoft faturate and contracted Capillaries 

 of the firft cut ft cm. 



In very hot weather many air bubbles 

 would rife, fo as to make a froth an inch 

 deep, on the top of the fap in the tube. 



I fixt a fmall air Pump to the top of a 

 long Tube, which had 1 2 feet height of fap 

 -in it; when I pumped, great plenty of bub- 

 bles arofe, tho* the fap did not rife, but fall 



■ 



a little, after I had done pumping. 



In Experiment 34. ( where a Tube was 

 fixed to a very fhort ftump of a Vine, with- 

 out any lateral branches) we find the ftp 

 rofe all day, and fafteft of all in the greateft 

 heat of the day: But by many obfervations 

 under the 37th and this 38th Experiments, 

 we find the fap in the tubes conftantly fab" 

 iided as the warmth came on towards the 

 middle of the day, and fafteft in the greateft 

 heat of the day. Whence we may reafon- 

 ably conclude, (confidering the great p er * 



fpira° 



I 



