





! 



■ 







I 





40 



T/e net able Statkh. 



o 



feet long i inch diameter, full of leaves, 

 and lateral moots to the tube t, 7 feet 

 long § diameter. (Fig. 3.) I ^ed the tube 

 with water, and then immerfed the whole 

 branch as far as over the lower end of the 

 tube, into the veffel u u full of water. 



The water fubfided 6 inches the firft 

 two hours (being the firft filling of the 

 fap veftels) and 6 inches the following night> 

 4 inches the next day 3 and 2 -\- % the fol- 

 lowing night. 



The third day in the morning I took 



the branch out of the water; and hung 



it with the Tube affixed to it in the open 



air ,- it imbibed this day 27 -|- 1 inches in 



12 hours. 

 This Experiment fhews the great power 



of perfpiration -, fmcc when the branch 

 was immerfed in the veffel of water, the 

 7 feet column of water in the tube, above 

 the furface of the water, could drive very 

 little thro' the leaves, till the branch was 

 expofed to the open air. 



This alfo proves, that the perfpiring mat- 

 ter of trees is rather actuated by warmth, 

 and fo exhaled , than protruded by the 

 force of the fap upwards. 



And 





. 







