138 Vegetable Staticks. 
what and where that power is which can 
be equivalent to that provifion nature has 
has made for the afcent of the fap in confe- 
quencc of the great perfpiration of the leaves. 
The inftances of the JefTamine tree, and 
of the Paflion tree, have been looked up- 
on as ftrong proofs of the circulation of the 
fap, becaufe their branches, which were far 
below the inoculated Bud, were gilded : 
But we have many vifiblc proofs in the Vine 
and other bleeding trees of the fap s reced- 
ing back, and pufhing forwards alternately, 
at different times of the day and night. And 
there is great reafon to think, that the fap 
of all other trees has fuch an alternate, re- 
ceding and progreffive motion, occafioned 
by the alternacies of day and night, warm 
and cool, moift and dry. 
For the fap in all vegetables does proba- 
bly recede in fome meafure from the tops 
of branches, as the Sun leaves them ; be- 
caufe its ratifying power then ceafing, the 
greatly ratified fap, and air mixt with it , 
will condenfe and take up lefs room than 
they did, and the dew and rain will then 
be ftrongly imbibed by the leaves, as is pro- 
bable from Exper. 42, and feveral others; 
whereby 
