SECT. XXIX. 9. RETROGRADE ABSORBENTS. 393 



but is made in the very mouth of the la&eals, as 

 was before explained. 



5, When chyle, milk, or other extraneous fluids 

 are found in the urinary bladder, or in any other 

 excretory receptacle of a gland ; no one can for a 

 moment believe, that theie have have been collect- 

 ed from the mafs of blood by a morbid fecretion, 

 as ii: contradicts all analogy. 



. Aurea chirse 



Mala ferant quercus ? NarcifTo floreat alnus ? 

 Pin^uia corticibus fudent eie&ra myricae? 



VlRGIl. 



IX. Retrograde Motions of Vegetable "Juices. 



THERE are befides fome motions of the fap in ve- 

 getables, which bear analogy to our prefent fubjecl: ; 

 and as the vegetable tribes are by many philofophers 

 held to be inferior animals, it may be a matter of 

 curiofity at leaf! to obferve, that their abforbent 

 veflels feem evidently, at times, to be capable of a 

 retrograde motion. Mr. Perault v cut off a forked 

 branch of a tree, with the leaves on; and invert- 

 ing one of the forks into a veffel of water, obferved 

 that the leaves on the other branch continued green 

 much longer than thofe of a iimilar branch, cut off 

 from the fame tree ; which fhews, that the water 

 from the vefiel was carried up one part of the fork- 

 ed branch, by the retrograde motion of its veffels, 

 and fupplied nutriment fome time to the other part 

 of the branch, which was out of the water. And 

 the celebrated Dr. Hales found, by numerous very 

 accurate expeiiments, that the fap of trees rofe up- 

 wards during the warmer hours of the day, and in 

 part defcended again during the cooler ones. Ve- 

 getable Statics. 



It 



