274 ON THE IRRITABILITY OF VEGETABLES, 



duced upon the spiral wires (before denominated spiral 

 vessels), and what she calls a leatherlike substance, by the 

 actions of heat, light, and moisture. I must confess, that 

 Mrs. Ibbetson has brought forward some strong proofs in 

 confirmation of her opinion ; but at the same time I must 

 acknowledge, that these proofs are not sufficient to convince 

 questioned, me, " that all plants are merely machines governed by light 

 and moisture, and that every idea of their sensibility or of 

 their volition, is only a proof, that we too often let our ima- 

 gination run away with our judgment:" which is the opir 

 nion of Mrs. Ibbetson, On the contrary I am still inclined 

 to believe, that plants are both sensible and irritable. As to 

 volition, I avoid saying any thing of this at present. In pro- 

 secuting this inquiry, it must be considered, that plants are 

 living organized bodies ; and of course, that they are at least 

 governed by the laws of vitality, if I may so express myself. 

 No mechanical machine is governed by such laws. Mis. 

 Ibbetson's opiaion with regard to the motions of the mimosa 

 sensitiva is certainly different from that which I entertain ; for 

 admitting all the mechanical structure mentioned, consisting 

 of " different joints, pullies, knots, and bolts," to exist in 

 the moving parts of plants, and that its spiral wires are ca- 

 pable of producing some of its motions ; yet I cannot con- 

 ceive, that either heat, light, or moisture, can possibly re- 

 gulate some of the beautiful and striking experiments, 

 which may be made either-on the mimosa sensitiva, m. pu- 

 dipa, or others. Indeed such a mechanical structure seems 

 to approach too near to the feeble works of men, and ap- 

 pears to me too complex (reasoning from analogy) to be the 

 production of the author of vatvre. It is proper here to re- 

 mark, that Mrs. Ibbetson's observations are mostly micro- 

 scopical, and hence I am induced to suppose (though with 

 the greatest deference to Mrs. Ibbetson's superior, abilities) 

 that possibly there may be some deception. But as I shall 

 probably take the liberty of addressing a few observations on 

 this important subject to Mr. Nicholson, after she has 

 finished what she intends to write. I must for the present 

 decline saying any thing farther ; except, that, should Mis. 

 Ibbetson well explain these observations, I shall then he 



ready 



