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CULTURE OF A FEW ORNAMENTAL PLANTS. 
light which blazed from a dark mass of lamp-black, excited to spontaneous com- 
bustion (as it is weakly termed) by electro-chemical agency. 
Light, it appears, is to vegetables the stimulus of the vital principle ; its opera- 
tion during the day affects the elaboration of the elements of water and carbon, 
producing the specific essences of the individual species. It is the chief agent of 
maturation, as well as of colour ; its absence during night, and in winter, produces 
torpor; and repose is as essential to plants as to animals. We cannot precisely 
trace the direct agency of light, because plants made the subjects of experiment 
are always placed in artificial situations ; but we shall not fail, from the observation 
of natural phenomena, to conclude that, every material change in the fluids is 
chemical— -if chemical, it must be electrical— and if electrical, we are inevitably 
led to the primary fountain of light. Thus all is harmony, perpetual routine ; 
verdure, maturity, all referable to the one great principle — the Sun ! 
CULTURE OF A FEW ORNAMENTAL PLANTS. 
In resuming our rambling notes on plants of this class, we may primarily advert 
to Lisianthus Russellianus , a species about which cultivators are very generally 
agreed in considering that it is one of the most difficult plants to preserve through 
the winter at present known. Being of biennial or perennial habitude, and never 
flowering before the summer or autumn of its second year s growth, it is thus im- 
possible to avoid keeping it at least one winter, and consequently the difficulties 
experienced must be fairly met and overcome. 
Unlike most other exotics, it seems incapable of reposing during the winter 
months, or of subsisting without the ordinary supply of heat and water. No plant 
is more susceptible of injury from cold ; as a low temperature, even when frost is 
excluded, will sometimes cause it to wither and die away entirely. The slightest 
drought in the soil also appears productive of the same results ; and we have 
observed the half of a fine stock of plants destroyed in the winter from one or both 
of these circumstances. In its decay, too, it is quite peculiar ; for as soon as the 
lower leaves begin to shrivel, without turning yellow, its loss may be calculated 
upon as inevitable, since it never recovers, and the mischief is speedily manifested 
on the whole plant. 
‘ We have seen many attempts, of various kinds, made to retain it in health for 
the winter season ; but those which have been most successful have always been 
based on the principle of keeping the plant constantly in a growing state ; and 
though we have no doubt other cultivators may have succeeded by adopting a 
different course, not having witnessed their systems, we can neither describe nor 
recommend them. 
To excite a plant to constant growth while nature is exerting her utmost 
