1 8 P^egetahle Statich, 
favour of the eminent Mr. Wife. Thh 
vine was prepared with a cover, as the Sun- 
flower was. Its greateft perfpiration in ix 
hours day, was 6 ounces -f- 240 grains ; its 
middle perfpiration 5 ounces 240 grains 
= to 9| cubick inches. 
The furface of its leaves was iSaofquarc 
inches, or 12 fquare feet 92 fquarc 
inches ; whence dividing 97 cubick inches, 
by the area of the leaves, it is found that 
tij part of an inch depth, perfpires off in 
12 hours day. 
The area of a tranfvcrfe cut of its ftem, 
was equal to of a fquare inch : hence the 
fap*s velocity here to its velocity on the fur* 
faceofthe leaves, will be as 1820 x 4 = 
72S0 : I . Then the real velocity ofthefap’s 
motion in the flem is = -iVi~ =38 inches 
in twelve hours. 
This is fuppofing the ftem to be a hollow 
tube: but by drying a large vine branch (in 
the chimney corner) which I cut off, in the 
bleeding feafon, I found the folid parts were 
J. of the ftem 5 hence the cavity thro' which 
the fap pafles, being fo much narrowed, its 
velocity will be 4 times as great, ^viz. 152 
inches in iz hours. 
But 
