C 18 ] 



on the other irregular bliflers; for 

 inftance, leaves of oak, which give 

 flat bliflers on the under fide, and 

 round bubbles on the upper fide. 

 Some form only thofe irregular blis- 

 ters at the upper fide, as the leaves 

 of fpurge, cataputia or euphorbia. 



Some leaves form neither bubbles 

 nor bliflers on either fide, and yet 

 yield a great deal of dephlogifticated 

 air ; for inftance,. leaves of nafturtium 

 Indicum: thefe leaves feem to have 

 a quality repulfive to water, which 

 only forms a kind of cover over the 

 furface of the leaves, without com- 

 ing into immediate contact. The 

 air oozing out of the leaves floats 

 under this cover, and rifes to the 

 higher!: part of the leaves, where it 

 forms a kind of bags, which at laft 

 detach themfelves from the edge> 

 and rife to the top of the jar. The 



leaves 



