80 Vegetahle Staiich. 



ther, fo as to let in air ; to prevent which in- 

 convenience, I further fecured the joynt 

 with the cement of Bees-wax and Turpen- 

 tine, binding a wet bladder over all. 



When the branch was thus fixed, I turned 

 it downwards, and the glafs tube upwards, 

 and then filled both tubes full of water ; 

 upon which limmediately applied the end of 

 my finger to clofe up the end of the fmall 

 tube, and immerfed it as faft as I could into 

 the glafs ciftern x, which was full of mer- 

 cury and water. 



When the branch was now uppermoft, and 

 placed as in this figure, then the lower end 

 of the branch was immerfed 6 inches in 

 water, viz. from r to i. 



Which water was imbibed by the branch, 

 at its tranfverfe cut i -, and as the water af- 

 cended up the fap veffels- of the branch, 

 fo the mercury afcended up the tube e z 

 from the ciftern x 5 fo as in half an hour's 

 time the mercury was rifen 5 inches and 

 I high up to z. 



And this height of the mercury did in 



fome meafure (hew the force with which the 



fap was imbibed, tho* not near the whole 



force 5 for while the water was imbibing, 



4 the 



