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SECTION XVIII. 



Leaves of plants die fooner when the 

 dephlogiflicated air, elaborated by 

 them, is feparated from them. 



WHEN the dephlogiflicated air, 

 fettled in the form of bubbles upon 

 the leaves, is fhook off, new bub- 

 bles fucceed ; and thus by making 

 off feveral times thefe air bubbles 

 a greater quantity of dephlogifli- 

 cated air is obtained. The fecond 

 crop of bubbles contains in general 

 a finer kind of air than the firfl ; 

 the reafon of which may be, that it 

 is fcarce poflible to free the furface 

 of the leaves entirely from all at- 

 mofpheric air flicking to them, par- 

 ticularly thofe which have a rough 

 F 4 niaggy 



