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early in the evening; for in-ftance ? 

 leaves of laurocerafus. 



Some leaves yield the air bub- 

 bles immediately, as leaves of pota- 

 toe plants; fome in a few feconds, 

 as mafioa\ fome in a ftw minutes* 

 as walnut trees; fome much later, 

 as leaves of laurocerafus. 



Some yield the air bubbles firft 

 on the under fide, as almoft all 

 leaves of trees; fome firft at the 

 upper fide, as leaves of laurocerafus \ 

 fome on both furfaces at the fame 

 time, as malva. 



On fome leaves the air bubbles 

 grow almoft all regularly one with 

 another, as in leaves of a vine, 

 waio-ut, lime tree; in fome they 

 are, from the very beginning, of a 

 very irregular fize, as in malva y 

 par Hey, &x- 



Thefe 



