ENGLISH EDITION. xiil 



explanation of common facts; and to introduce little beyond 

 that which every gardener can verify for himself. Vegetable 

 anatomy is no doubt the foundation of all correct views of 

 physiological action ; chemistry is of the first importance, when 

 the general functions of plants are considered in a large and 

 general way; and electricity probably exercises an important 

 influence over the vital actions of all living things. But these 

 are the refinements of science, belonging to the philosopher in 

 his laboratory, and not to the worker in gardens ; they are 

 indispensable to the correct appreciation of physiological 

 phenomena, but not to the application of those phenomena to 

 the arts of life ; electricity, in particular, appears to me, in the 

 present imperfect state of our knowledge of its relation to 

 vegetable functions, altogether incapable of forming a part of 

 any horticultural theory. 



What the gardener wants is, not a treatise upon botany, nor 

 a series of speculations upon the possible nature of the influence 

 on plants of all existing forces, nor an elaborate account of 

 chemical agencies inappreciable by his senses and obscurely 

 indicated by their visible results; but an intelligible explanation, 

 founded upon well ascertained facts, which he can judge of by his 

 own means of observation, of the general nature of vegetable 

 actions, and of the causes which, while they control the powers 

 of life in plants, are themselves capable of being regulated by 

 himself. The possession of such knowledge will necessarily 

 teach him how to improve his methods of cultivation, and lead 

 him to the discovery of new and better modes. 



It is very true that ends of this kind are often brought 

 about by accident, without the smallest design on the part of 

 the gardener ; and there are, doubtless, many men of unculti- 

 vated or idle minds, who think waiting upon Providence much 



