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Secr. Il. 8. MBSORBENT:VESSELS. 17 and LIT. of Grew’s Anatomy of Plants(fol. edit.), and by this eafy experiment both that abforbent fyftem, st imbibes nourifhment from the earth, and brinss it to the caudex of‘each bud; and that which imbibes moifture from the air, and à part of the perfpirable matter on the- face of the leaf, and brings it to the caudex of each

1

bud, are agrc eeably demonftrated. See Plate IT. Fig. 1. And that thefe

veflels of large diameter, with their fides confifting of a fpiral line, are not arteries or veins, is evinced by infpeéting a ftem of euphor- bia, fpurge; or the ftalk of a fig-leaf, ficus, immediately on dividing them, as the milky juice ooZes from a ring of veflels exterior to thote are abforbents.

Secondly, that thefe veffels are not furnifhed with frequent valves is countenanced by the experiments before mentioned in No. 5 ofthis FER one of which confifted of lighting a piece of cane, and draw-

no the fmoke through it, as through a tobacco-pipe, in either direc-

ae: and the other in phacing a bit of recent twig with one end of 1t in a cup of water in the receiver of an air-pump,. and caufins both

air and water to pafs through it in either direction.

a fimilar ftruc-

P £ )I

If the minuter branches of vegetable a bforbents be c

Qure, TE 1S ea{y to conceive how a vermicular or perutaitic motion of Li: es nn|: the veflel, beginning at the loweft part of it, each fpiral ring fuc-

ceflively contraéting itfelf,#07 16 fills up the tube, muft forcibly pufh

forwards its contents without the aid of valves; ne if this vermicular

cs motion fhould begin at the upper eud Lof the veflel, it muft with equal facility carry its nAnEd fluid 10 a en or contrary direétion.

9 As the abforbent veffels in the roots of plants are protected from the froft in forme degree. by the earth w hich covers them; they

DÉAT C: BB PAS LAN AA LME RES FA: An reg A Fe QE feem at all times to be fuicientls alive to drink up and pufñh for

wards their adapted fluid, fince if a branch of a tree is brought into a warm room, it.will in general pullulate in-the winter, as the veffels of the upper part of the> branch are rendered fufficiently 1r- he abforbents of

nitable by warmth to 2 in concert with t D Neverthelefs,