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plants, that were not immediately exposed to 

 its perpendicular effect : therefore the front 

 windows may be kept open continually, unless 

 there is a prospect of its being particularly 

 severe, or accompanied with cold driving 

 winds, in which case it will be necessary to 

 have them pretty close. 



If air is too sparingly admitted at this season, 

 when many of the plants have not yet finished 

 their summer's growth, it will inevitably cause 

 them to produce weak, and tender shoots ; 

 which will be extremely liable to damp off at a 

 more advanced season, when the house must 

 be unavoidably kept close on account of the 

 severities of the external air; and besides, it will 

 tend to give them a more general tender habit, 

 and render them less able to resist the winter 

 colds than they otherwise would. Hence it is 

 evident, that they cannot receive too. much air, 

 whenever the state of the external air will 

 admit of it, by being free from all appearance of 

 frost ; as it will be so much to their advantage 

 to be thus hardened, before the winter assumes 

 its severest front. 



This is a practice I would strenuously re- 

 commend to all cultivators of exotics, to 



