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HYPERICUM CALYCINUM, FOR SHRUBBERIES, &c. 
certain fluids, which are destined to be the colouring media. In the absence of 
proof, we may still appeal to a few facts adduced by several authorities. 
Influence upon leaves — developing Chlorophyll. — It frequently happens in 
America that clouds and rain obscure the atmosphere for several days together, and 
that, during this time, buds of entire forests expand themselves into leaves. " These 
leaves assume a pallid hue, till the Sun appears, when, within the short period of six 
hours of a clear sky and bright sun, their colour is changed to a beautiful green." 
In Sillimans Journal, a circumstance of this kind is recorded, whereby 
it appears that in six hours the tinting of several miles of a forest went through all 
the grades, from that of a greenish-white to full spring verdure. 
Every gardener is conversant with the variations of colour which flowers 
assume under artificial treatment : thus, Andromeda polifolia, and Kalmia latifolia, 
are purple or pink when growing in the open air, but become nearly white when 
made to flower under glass. Now, it is not the heat altogether that influences the 
flower, but light, modified by passing through glass. Hence, we should study the 
effects of all those degrees of heat in which any tender or half-hardy plant can 
thrive, and adapt them to the actual volume of clear sunlight, because a heated 
atmosphere is not a substitute, — or, at least, a very defective one — for the clear 
ray, inasmuch as it (heat) produces no chemical effect upon the fluids of either leaf 
or flower. 
Light acts beneficially upon the upper surface of the leaves, and hence great 
caution is indicated in allowing space sufficient for full play and action; it also pro- 
motes the transpiration of superfluous moisture and gases ; and these appear to 
transude chiefly through the stomates of the under surfaces. 
We begin to acquire fresh evidence of electric action in the new experiments 
upon corn-growing when exposed to the agency of electric circuits. All nature, 
air, water, earth, are replete with masked light, and this can be derived only from 
the Sun : if then it become a well established fact, that the growth of plants can 
be doubly stimulated by electricity derived from the atmosphere, we establish that 
most important point — the electrizing principle of the Sun's rays. In a few months 
we hope to collect, and be enabled to adduce, facts in proof of the theory thus 
cursorily hinted at. 
HYPERICUM CALYCINUM, FOR SHRUBBERIES, &c. 
There is no part of an extensive garden — nor indeed of a small one — -however 
remote its position, or however insignificant a feature it may form of the whole, 
that can properly be deemed unworthy of some attention and exertion to invest it 
with an ornamental appearance. The rudest and most uncultivated portions 
require, in fact, as much skill and consideration in their adornment as the most 
finished and elaborate parterre ; and it is in the selection and chaste fitting of 
