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THE GARDENER. 



colour and flavour, and by its gaseous fluids imparts 

 nourishment and vigour. Stagnant air, so prejudicial 

 to the human frame, is also unheal thful to plants in 

 full vegetation. Yet moist air charged with electric 

 matter, so oppressive to animals, gives increased acti- 

 vity to plants; and diy air, so good generally for the 

 former, is injurious to the growth of the latter ; and 

 putrid exhalations which are fatal to mankind, become 

 the means of supporting the vegetable world, w^hich 

 is made to consume the substance which otherwise 

 would be noxious to us. 



Surely in the consideration of such matters there is 

 pleasure and profit ; yet though the functions of plants 

 may be understood in their general principles, there 

 are many points little, if at all known, which relate to 

 their food. For instance, the application of an appa- 

 rently inert substance, such as gypsum, (plaster of 

 Paris,) promotes the growth of certain plants, and yet 

 the manner in which it acts, the modus operandi^ as 

 it is tenned, is not understood. The poorest sand or 

 brick-dust, which possesses no nutritive qualities, if 

 scattered on grass land causes very perceptible effects, 

 and produces white clover where it had not previously 

 appeared ; but w^ho can explain the nature of the in- 

 fluences which produce the vegetation ? 



As to soils^ it is not enough to be aware that a 

 loamy and deep mellow soil, free from stones, is the 

 most desirable ; that an intractable argillaceous clay, 

 being too retentive of moisture, is unfit for a garden ; 

 and that a very sandy soil, from the contrary defect, is 

 unfavourable. The Gardener should be able to dis- 

 tinguish the degrees in which there is an excess or 

 deficiency of any component parts, to know the means 

 of remedy, and the proper adaptation of his plants to 

 his soil, of whatever kind it may be. He may judge 

 correctly by his senses, that dark-coloured earth is 

 generally the best ; yet it may be too light and loose 



