VEGETABLE STiTUCTURE. 
v3 
'Cd to that efTential part the Fletli of the Root : and after this the fydeni 
of Evaporation ferves the excellent purj^ofe of difeharging that moiilure 
which had been drained off its ufeful parts, and uiaking room for more. 
Thus is a continual fupply of frefh moifUire received ; and from ir, by 
peculiar fecretions, that part is feparated which can incrcafe the bulk of the 
Plant: This part is delivered to the Flefli, whofe Velfcls all returning 
upon themfelves, it is carried round, in a circulatory motion. The diflen- 
tion and contradtion of the Flefli, and other parts, from the various de- 
grees of heat in the Atmofbhere, giving the mot'on ; and the Valves in 
the Flefh-Vcflels, which open only one way, diredling the courfe. From 
the Flefli are fent the Conic C'lufters of Veflels into all parts of the Plant, 
which alfo give that kind of fecondary Circulation we have named ; and 
From the abundance of Juice in the Flcfh, thus fed by tiie Roots and 
Leaves, riles a portion which forms a Stalk. In the moll fimple khids, as 
CoLCHicuM, even this intermediate part is wanting; in the Aconite it 
rifes a few inches, and then breaks into a Flower, where the Rudiment of 
new Plants are formed ; but in the Anemone, the Flower being raifed 
higher, there is a fecond growth of Stalk, the part above the Leaf riling 
from the arch of the Flefli at that Joint, jufl: as the lower part did from 
the Root. Thus is a more complex Vegetable Body nourilhtd by two 
circulatory fyflems, as a more Ample one was by one fuch fyflem ; and it 
is eafy to fee from this, that in order to fupport the largefl and moll cem- 
plex of all, there can require only fo many mere repetitions of the origi- 
nal circulatory fyflem. 
They erred who fancied a Circulation in all the parts of fdants ; for 
the ufe of the exterior Coats is merely Absorption and Evaporation ; but 
I muft be allowed to fay, fince thefe plain fads confirm it, that neither 
were they right who thought Abforption and Evaporation gave growth to 
the efiential parts of Vegetables. The Circulatory Syflem lies deep, and 
has not been obferved : the attention of the Curious being fixed on one 
point, drew their followers from the other. It is certain, that without 
that great operation the Evaporation by means of the Leaves and other 
parts open to the air, the Juices of the circulatory fyflem could not be fed j 
for the fame exhaufled moiilure v/ould remain in the Plant : but, on the 
other hand, it is equally certain, that a vegetable body may be kept alive 
without the afliflance of that operation. This is feen in thofe tuburous 
and bulbous Roots which, for many months, have no Leaf, or other 
part above the ground, yet continue alive and healthy ; and are ready, 
upon a change of the flate of the air and earth, by heat and moiflure, to 
Shoot 
