J/egetable Stattch. 137 
for the fine capillary veflels to exert their 
vaftly attrafting power, which perfpiration 
is efFeded by the brisk ratifying vibrations 
of warmth : A power that does not feem 
to be any ways well adapted, to make the 
fap defeend from the tops of vegetables by 
different veffels to the root. 
If the fap circulated, it muft needs have 
been feen defeending from the upper part 
of large gafhes, cut in branches, fet in wa- 
ter, and with columns of water preffing on 
their bottoms in long glafs tubes, in Exp, 43, 
and 44. In both which cafes, it is certain 
that great quantitigB of water paffed thro’ 
the ftem, fo that it muft needs have been 
feen defeending, if the return of the fap 
downwards were by trufion or pulfion, 
whereby the blood in animals is returned 
thro’ the veins to the heart; And that pul- 
fion, if there were any, muft neceffarily be 
exerted with prodigious force, to be able 
to drive the fap thro’ the finer capillaries. 
So that if there be a return of the fap down- 
wards, it muft be by attraction, and that 
a very powerful one, as we may fee by many 
of thefc Experiments, and particularly by 
Experiment x i . But it is hard to conceive, 
what 
