1 44 ^^- Per civ al on the 



ther the atmofphere be dry or moifl: j and in- 

 flantly clofe v/hen certain chemical ftimuli, fuch 

 as the vapour of vol. alkali, or the fumes of 

 burning fulphur, are applied to them. Thefe 

 conclufions were founded on the recolleflion of 

 experiments which I made more than twenty 

 years ago. But the Abbe Barthalon de St. 

 Lazane, in a late treatife on the eleflricity of 

 vegetables, has adopted an oppofite hypothefisy 

 and adduced the following trials in fupport of 

 it. When the fenfitive plant, fays he, is touched 

 with a piece of polifhed metal, terminated at 

 each end by a round knob, its leaves fhrink 

 back and fliut. When it is touched with a 

 piece of glafs, of the fame form, it remains in- 

 fenfible. But if this piece of glafs be eleftrified, 

 and the plant be touched with it in this ftate, 

 the leaves inftantly clofe themfelves. Hence 

 he infers, that the plants called Mimofae are 

 endued with a much greater portion of eledrical 

 fluid than others ; that this fluid efcapes when 

 touched by a foreign body, capable of convey- 

 ing it away; and that they flirink by being thus 

 deprived of what >s eflential to their health and 

 vigour.* 



1 have lately procured a fenfitive plant, with 

 the defign of repeating the Abbe's experiments. 



• 



See Abbe Barthalon de St. Lazane D'Ekaricite das 

 Vegeteaux : Alfo Appendix to Monthly Review, vol. XVII. 

 p. 135- 



But 



