96 
ladies’ flower gardener. 
is the oxygen, the nitrogen being little else than a diluent tc 
modify the strength of the oxygen. It was long believed by men 
of science that plants possessed the power of exuding oxygen, 
and so formed a prime agent for restoring vitiated air to purity. 
Later investigations, however, chiefly by French chemists, have 
made it evident that plants have no such power, unless when 
placed under the influence of the sun’s rays, or, in other words, 
that solar light is the grand cleanser of the atmosphere, and with¬ 
out which both plants and animals languish and die. With 
respect to plants in particular, it is ascertained that, while inhaling 
oxygen and expiring carbonic acid, their leaves possess the 
remarkable property, in conjunction with the sun’s light, of 
re-transforming the carbonic acid into oxygen. At night, when 
the light of day has departed, the expired carbonic acid may be 
detected in the neighborhood of plants; and hence one cause of 
injury to health by breathing night air ; but when the morning 
sun again bursts upon the scene, a great chemical process com¬ 
mences in the atmosphere—the carbonic acid is decomposed, 
oxygen is evolved, and all nature rejoices in a recreation of its 
appropriate nourishment. 
A question will here readily occur—what species of plants are 
best adapted for these domestic greenhouses ? We are fortu¬ 
nately enabled to answer this inquiry by referring to a learned 
paper on the subject by Mr. Ellis, which was read to the Botani¬ 
cal Society of Edinburgh, January 13, 1839, and afterwards, 
published in the Gardener’s Magazine, and also as a separate 
pamphlet. According to this gentleman’s statement, the plants 
most suitable are “ those which partake largely of a cellular 
structure, and possess a succulent character, and especially those 
which have fleshy leaves ; whilst, on the contrary, the continued 
humidity is unfavorable to the development of flowers of most 
exogenous plants, except such as naturally grow in moist and 
shady situations.” Plants, therefore, which have to grow and 
