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(2) $. 19. 
(c) Lib. 1. 
67+ $+ 14. 
(d) P.2.$. 
21. 
(e) Ib. 
OF the Wecesasion sia 
that Plant. For befides Water, and Earth, an Alkaline Salt and Oy! are, 
as is faid, the predominant Principles of thefe Vefels. (a) Tt isthenthe 
Oyl, chiefly, by which thefe Vefels are Tough: for being of a tenacious 
Nature, by taking hold of other Prizciples, it marries them together 5 
and the Alkaline Salt and Earth, concentred with it, addeth to it 
more Strength. Hence the Capt Mortunm of moft Bodies, efpeciall 
thofe that abound with Oy! and a sal Alkali, is brittle and friable’; 
thofe Prizciples, which were the Ligaments of the reft, being forced 
away fromthem. From the fame Caufe, the Parenchymous Parts of a 
Root, even in their Natural State, are brittle and friable; fc. Becaufe 
their Earthy, and efpecially Oleous and Saline Principles are, as is faid,(b) 
fo very few. Therefore all Piths and more fimple Parenchyma’s, break 
fhort , fo Corn, and the Roots of Potato’s, and divers other Plants, 
being dryed, wil! eafily be rub’d to Meal; and many Apples, after 
Frofts, eat mealy 5 the Parenchymous Parts of all which, are not only 
by Avalogy, but in Subftance or Effence, the felf fame Body. (c) 
31. §. And asthe Confiftence of the feveral Organical Parts, is de- 
pendent on their Prizciples; fo are their Figures. And firft, the 
Succiferous Vefels, from their Alkaline Salt, (d) growin Length. For 
by that Dimenfion, chiefly, This salt always Jhoots: And being aleG 
moveable Principle than the reft, and {o apt more fpeedily to fix or 
shoot : It thus overrules them to its own Figure. And even as the Shape 
of a Button dependeth on the Mould, the Si/k and other Materials 
wrought upon it, being always conformable thereunto: fo heres the 
galt is, as it were, the Mould; about which, the other more paffive 
Principles gathering themfelves, they all confort and fafhion to it, 
Hence alfo the fame Sap-Veffels are not pyramidal, asthe Veins of Ani- 
mals 5 but of an equal bore, from end to end; the Je of the 
faid Sa/t, being alfo figured more agreeably to that Dimenfion. And 
as by the Saline Principle, thefe Vefféls are Long 5 fo by the Oleous, (e) 
they are every where Round, or properly Cylindrical; without fome 
joynt Efficacy of which Principle, the faid Vefels would be Flat, or 
fome way Edged and Azgular, as all faline fhoots, of themfelves, are 5 
as thofe of Alum, Vitriol, Sal Ammoniac, Sea Salt, Nitre, &c, And 
becaufe the Spzrituous and more Fluid part of the Primciples, is leatk 
of all apt to fix 5 while therefore, the other parts fix round about, 
This will remain moveable in the Cevtre s from whence every Veffel is 
formed, not into a folid, but hollow Cylinders thatis, becomes a 
Tube. 
32. §. The Laiiferous Veffels are tubulary, as the Lymphedués, 
but of a fomewhat wider Concave or Bore. For being their Princi- 
ples-are lefs Earthy and Oleows, and alfo more loofely Concéntred 3 as 
from their eafie corruption or Re/olution by the Aer, it appears they 
are: they are therefore more tender, and fo more eafily dilative, and 
yielding to the faid spirituous part in the Centre. And by this means, 
obtaining a wider Bore, they are more adapted to the free motion of 
the Milky Content: which being an Oleous and Thicker Liquor, than 
that in the Lymphedudts 5 and having no advantage of pulfation, as the 
Blood hath in Animals might fometimes be apt to f{tagnate, if the 
Vefels, through which it moves, were not fomewhat wider: 

33. §. 

