
Book II of Roots: 99 
SS SSS 
Aer-Vefels. This Connexion [have no where fo well feen, as in the 
White Bottoms of the Bladders of a Bulrufh, being cut traverfe 3 where- 
in they have the appearance, -of very Fine and clofe Needfe-work. 

to. §. The Fibres by which the {aid Threds are knit together, I 
think are all Single: and are feldom aid fcarcely vifible, except by 
obliquely Tearing the Pith ; by which means, they will appear through 
the Glafs, broken off, fometimes, a quarter or half an Inch, or an 
Inch in Length; and as {mall as one Single Thred of a Spiders webb. 
In a Bulrufh, they are fometimes difcernable in cutting by the Length. 
Thefe Fibres, and the Threds , they knit together, for the moft part, 
are fo pellucid, and clofély fituate, that they frequently feem to 
make One entire Body, as a picce. of Ice or a film of Water it 
felf: or even as Avimal skins fometimes thew, which yet are known 
to be Fibrous. 
_ U1. §. The Situation of thefe Threds, is contrary to that of the 
Veffls, as thofe by the Length, fo thefe, chiefly, by the Bredth of the 
Root,or horizontally, from one edge of the Pith to the other. They are 
continued circularly ; whereby, as oft as they keep within the compafé 
of the feveral Bladders, the faid Bladders are Round: But where they, 
winde out of one Bladder, into another, they mutually Interfe@ a Chord 
of their feveral Circles ; by which means, the Bladders become Angu- 
lar. 
12. §. The Contexture, likewife, both of the Parenchymous Part 
of the Barque, and of the Diametral Portions inferted betwixt the Lig- 
nous 5 isthe fame withthis ofthe Pith, now defcribed 5 that is, Fibrous. 
Whence we underftand, How the feveral Braces and Threds of the Vef- 
Jels are made : “For the Vefels running by the length of the Root, as the 
Warp 5 by the Parenchymous Fibres ranning crofs or horizontally, as 
the Woof: they are thus Avit and as it were ffitched up together, 
Yet their wefiage feemeth not tobe fimple, asin Cloath ; but that 
many of the Parewchymous Fibres are wraped round about each 
Veffel ; and, in the fame manner, are continued from one Veffel to 
another; thereby knitting them altogether, more clofely, into one 
Tubulary Thred and thofe Threds, again, into one Brace: much af- 
ter the manner of the Needle work called Back-Stitch or that ufed in 
Quilting of Balls. Some obfcure fight hereof, may be taken in a Thred 
ofCambrick, througha Microféope. But it is moft vifible, inthe Leaves 
and Flowers of fome Plants, The Delineation of thefe Things I fhall 
therefore omit, till we come hereafter to fpeak of the other Parts. 



13. §. From what hath been faid, it may be conjectured ; That 
the Aer Veffels facceflively appearing in the Bargue, are formed, not 
out of any Fluid Matter, asare the original ones ¢ But of the Parenchy- 
mous Fibres; fe. by changing them from a Spherical to a Tubulary 
Forme. 
14. §. From the precedents, it is alfo manifeft, That all the Paren- 
chymous Parts of a Root, are Fibrous. 
t5. §. And laftly, That the whole Body ofa Root, confifteth of 
Veflsand Fibres, And, That thefe Fibres themfelves, are Tubulous, 
or, 
































