Vegetable Staticks. 87 



was -J of an inch: The great end of this branch 

 I put into the cylindrical glafs e r 3 which 

 was an inch diameter within, and eight inches 

 long. 



1 then cemented fa ft the joint r, firft fold- 

 ing a ftrap of fheeps-skin round the ftem, fo 

 as to make it fit well to the tube at r ; then 

 I cemented faft the joint with a mixture of 

 Bees-wax and Turpentine melted together in 

 fuch a proportion, as to make a very ftifF 

 clammy pafte when cold, and over the cement 

 I folded feveral times wet bladders, binding 

 it firm with packthread. 



At the lower end of the large tube e was 

 cemented, on a leffer tube z e, £ inch dia- 

 meter in bore, and 1 8 inches long : The fub- 

 ftance of this tube ought to be full | of an 

 inch thick, elfe it will too eafily break in 

 making this experiment. 



Thefe two tubes were cemented together 

 at e, firft with common hard brick-duft ce- 

 ment to keep the tubes firm to each other ; 

 but this hard cement would, both by being 

 long moift, and by the different dilatations 

 and contractions of the glafs and cement, 

 feparate from the glafs in hot weather, fo 

 as to let in air ; to prevent which incon- 

 venience, I further fecured the joint with 



G 4 the 



