1 1 8 Vegetable Staticks. 
was much fap loft, the fap would fubfide in 
the firft tube 5 but they would not afterwards 1 
have their fap in Equilibrio ; i. e, the furface i 
of the fap in each was at very unequal heights ; :i 
the rcafon of which is, becaufe of the diffi- i 
culty with which the fap paffes thro' the ^ 
almoft faturate and contrafled Capillaries ’j 
of the firft cut ftem. 
In very hot weather many air bubbles ! 
would rife, fo as to make a froth an inch i 
deep, on the top of the fap in the tube. i 
I fixt a fmall air Pump to the top of a 
long Tube, which had 12 feet height of fap 
in it j 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 ftiort flump of a Vine, with- 
out any lateral branches) we find the fap 
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 fub- 
fided 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 per- 
