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siderable encrease of water, which may now 

 be copiously given to them, particularly the 

 more free growing kinds ; but let the following 

 be observed as a general maxim, not to be de- 

 parted from ; that it is necessary to the health 

 of plants, especially the tenderer species, to be 

 permitted to become moderately dry, before 

 they are again watered ; because, when kept 

 in a continual wet state, the mould becomes 

 entirely destitute of that active quality, so indis- 

 pensably necessary to vegetation; and the plant 

 in consequence, will assume a very unhealthy 

 appearance : which many might perhaps not 

 attribute to the proper cause. 



There are a few plants which rank amongst 

 the inmates of the green-house, which require 

 to have their roots constantly covered with 

 water; these we term aquatics; they are some- 

 times introduced in pots, tubs, troughs, cis- 

 terns, or basons, according to the fancy of the 

 cultivator, any of which, when used for this 

 purpose, must be made sufficiently tight to 

 retain the water put into them. 1 shall give 

 some directions concerning the planting, and 

 management of these plants, when treating on 

 the consetvatory ; to the ornament of which 



