WINDOW AND ROOM PLANTS 187 



We have said that the cultivation of room plants is beneficial, 

 and in this connection it may be well to say a word on the 

 influence of plants on health. The budding student will tell you 

 that the animal world inhales oxygen, and exhales carbonic acid, 

 thus vitiating the air; but that plants inhale carbonic acid, and 

 build up the carbon into their system. So far good, the plant 

 restores nature's balance by taking from the air the impure 

 substance which the animal has poured into it. But the budding 

 student goes further; he tells you that the plant's functions are 

 reversed at night, and consequently, that while a collection of 

 plants in a room is healthy during the day, it is unhealthy after 

 nightfall. If this were strictly correct it would be a somewhat 

 serious matter, for it would show that plants are a source of 

 danger in bedrooms, and must certainly be kept out of the rooms 

 of invalids. But it is not entirely accurate. The change in the 

 functions of the plant ought rather to be described as suspension 

 than reversal. Certainly, so far as respiratory action is concerned, 

 the presence of a plant or two in a bedroom cannot be regarded 

 as inimical to the health of human beings ; and one gas-jet 

 with an ill-fitting burner, still more one stuffed chimney, or one 

 window that will not open, will do far more harm. Any one who 

 has the least fear of evil consequences, yet does not like to discard 

 his plants, may rest assured that if he will remove the stuffing 

 from the chimney, and keep his bedroom window open all night, 

 he will never suffer from the respiratory processes of plants. 



There is, however, another matter to be considered, and that 

 is the perfume of strongly scented flowers. This certainly has a 

 deleterious effect on some persons, even when they are in health. 

 Here the " personal equation " comes in. There are instances on 

 record of a brave soldier trembling violently merely because a cat 

 came near him. One person will enjoy the odour of a Hyacinth ; 

 another will be overcome by it. Experience will soon teach 

 valuable lessons on this matter. Strong-smelling flowers must 



