•7. 



)rk 



s 



r 



iced 

 row 



e 



tree 

 rth, 

 •res, 



?pe- 

 unor 



ther 

 ted, 



o 



:oii- 



rec- 



lals, 

 fail. 



I 



the 



iwn- 

 in of 

 feof 



•effel 

 inaal 

 as 3 



d 



an 



geft, 



n 



,Ll' 



an 



Sect. II. 8. 



ABSORBENT VESSELS. 



\ 



^7 



lid Lll. of Grew's Anatomy of Plants (fol. edit.), and by this eafy 



p^rime 



both that abforbent fyflem, which imbibes nouriOi 



from the earth, and brings it to the caudex of each bud ; and that 



w 



ich 



bibes moift 



from th 



nd a part of the perfpirabl 



matter on the furface of the leaf, and brings it to the caudex of each 

 bud areat^reeably demonftrated. See Plate II. Fig. i. And that thefe 



ifc 



of laro-e diameter, with their fides confiding of 



line,. 



are not arteries or veins, 



is evinced by infpe£ling a flem 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 vellels exterior to thofe 



r 



large abforbents. 



Secondly, that thefe vefTels are not furnlfhed with frequent valves 

 is countenanced by the experiments before mentioned in No. 5 of this 

 fedion, one of which confifted of lighting a piece of cane, and draw- 



ing 



the fmoke through it, as through a tobacco-pipe, in either d 



P 



d the other in placing a bit of recent twig with one end of it 

 of water in the receiver of au air-pump, and caufing both 



* 



air and water to pafs through it in either diredion. 



If the minuter branches of vegetable abforbents be of a iimilar ftruc- 

 ture it is eafy to conceive how a vermicular or periftaltic motion of 

 the veiGTel, beginning at the loweft part of it, each fpiral ring fuc- 

 cefTively contrading itfelf,' //// It fills up the tube, muft forcibly pufii 

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

 motion fhould begin at the upper endof the veflel, it muft with equal 

 facility carry its contained fluid in a retrograde or contrary direaion. 



8. As the abforbent veflels in th 



of pi 



are protected 



from the froft in fome degree by the earth which covers them ; they 



up and pufh for- 



drink 



fince if a branch of a tree is brought into 



feem at all times to be fufficiently 

 wards their adapted fluid, 

 a warm room, it will in general pullulate in the winter, as foon as 

 the veflels of the upper part of the branch are rendered fuflSciently ir- 

 ritable by warmth to ad in concert with the abforbents of the root^ 



D Nevertheless 



