158 Vegetable Staticks. 



bark was well dried j after which I fet it 

 upon the air-pump, and exhaufted the air; 

 upon which the air iflfued as freely at x, as 

 it did before the bark had been wetted, and 

 continued fo to do, tho' I kept the receiver 

 exhaufted for many hours. 



I fixed in the fame manner as the pre- 

 ceding Birch-ftick, three joints of a Vine- 

 branch, which was two years old, the up- 

 permoft knot r being within the receiver; 

 when I pumped 5 the air pafled moft freely 

 into the water x x. 



I cemented faft the upper end of the flick n, 

 and then pumped; the air ftilliflued out at at, 

 tho* I pumped very long 5 but there did not 

 now pafs the twentieth part of the air which 

 pafled when the end n was not cemented. 



I then inverted the flick, placing n fix 

 inches deep in the water, and covered all the 

 bark from the furface of the water to z 

 the top of the receiver with cement j then 

 pumping the air which entered at the top 

 of the ftick, pafled thro' the immerfed part 

 of the bark: When I ceafed pumping for 

 fome time, and the air had ceafed iflliing 

 out; upon my repeating the pumping it 

 would again iflue out. 



I found 



