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30 



UMBILICAL VESSELS. 



Sect. III. 11. 5. 



lower than the origin of this branch did not bleed. 



This 



may 



be 



2: at 



d 



accounted for from the afcent of the fluid in thefe veffels bein 

 this time principally owing to the action of their abforbent mou 

 and to their confifting of long cylinders with' minute diameters 

 rigid coats, like thofe which are vifible to the eye in dry cane, through 

 which fmoke will pafs in either diredion, and which at this early fea- 

 fon may not be excited into vegetable adion ; there is neverthelefs a 

 power of abforp 

 fon. 



(ling in any part of them in the warmer fea 



becaufe a branch or flower-ftalk cut frqm the root, and fet 



glafs of water, will drink up a confiderable quantity of 



Th 



ere is 



Ifo a fituation in their difeafed or dead flate. wh 



they appear to 



a6l for fome years like capillary tubes, as in the decorticated part of 

 pear-tree, defcribed in Se£l. XV. 2, 3. 



. 5. During the great adion of thefe umbilical abforbent vefTels the 

 buds become expanded, that is the young vegetable beings put forth 

 leaves, which are their lungs, and confiH: of a pulmonary artery, vein, 

 and abforbents, and alfo acquire a new bark over that of the branches. 



nk. and 



of the lafl: year, which confifls of 



arteries. 



veins, and abforbents, and new radicles, which terminate in the foil 

 At this time the umbilical vdflels, which exifted in the alburnum. 01 



fap-wood 



fe to adt 



d coalefoe 



folid wood, perhaps 



fimply by the contradion of the fpiral fibre, of which they are com- 

 pofed ; and the fwarm of new vegetables, which conftitute a tree, are 

 now nourifhed by their proper ladeal and lymphatic fyftems. 



A curious circumftance now occurs, which is that wherever a tree 

 13 now wounded, no moiflure appears. On the contrary, the wound 

 from Dr.Hales's experiments is in a flrongly abforbing ftate, infomuch 

 that on applying water to wounds made in the fummer feafon, it was 

 found to be drank up with great. force, as was ingenioufly fhewn 

 mercurial fyphons contrived to refift its abforption. 



This evinces, that though during the bleeding feafon in the vernal 

 months the fap-juice is imbibed by the umibilical abforbents, and car-, 



ried 



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