47 



only ascend to the celling; and there remains only so long as 

 it is of a higher temperature than the air nearer the floor. 

 When it lias gradually given out its excess of heat, it becomes 

 of the same density as the rest of the atmosphere, mingles 

 with it, and as it falls to our level we are in danger of inhaling 

 it a second time, or perhaps oftener. From this it is evident 

 that the aperature tlirough which tliis Impure or vitiated air 

 escapes should be near the ceiling of the room, or if for plants 

 in a window, it should be near the top, but it must be remem- 

 bered that no air can escape from any room unless an equal 

 quantity enters to supply its place; hence it is necessary to 

 make provision for the admiesion of pure air. A very good 

 mode for the emission of foul air is to make a funnel shaped 

 hole in the chimney, and liave a zinc funnel made to fit it 5 

 securely fasten the funnel in the hole; through this funnei 

 most, if not all, the impure air will pass, and will be carried 

 off by the upward current in the chimney; to supply the place 

 made vacant by the egress of this air, a door may be opened, 

 or if this is not practicable, some other mode will suggest it" 

 self, but recollect ilmt cold draughts are injurious to yourself 

 as well as to the more tender plants ; the upper sash of the 

 window ma3' be lowered, or if the weather is mild, the upper 

 maj' be lowered and the lower one raised, or one or both may 

 be taken out. You canimt give plants too much fresh air, pro- 

 vided the air is not chilling to their nature. 



Light is as needful to the health of plants as air, and its 

 absence in sufficient quantity is the cause of a great disap. 

 pointment to many amateurs. All i3lants need light; some, 

 we know, cannot endure the direct rays of our summer sun- 

 light; they are the inhabitants of our woody vales and hill- 

 sides, where they are protected by the foliage of the lords o^ 

 the forest; there they grow to perfection ; among these may 

 be noted the ferns and mosses, some of which, if exposed to 

 the fierce rays of old Sol for one half hour, would not recover 

 from the effects of the injury for months. There are other 

 plants that will delight in the sunshine in the morning, but 

 prefer to have some shade in the afternoon. Among these 

 may be noted the Golden Tricolor Geraniums ; they need some 

 sunlight to bring forth their bright colors, yet if exposed too 

 much, the delicate tints which make them so lovely, will fade 

 away lilvC the mists in the morning. There is still another 

 class that want all the light they can get, and if thej^ don't get 



