82 
RETROSPECT OF THE LATE WINTER, 
I 
cooled in Spain and India by being put into porous eartlien vessels ; and, secondb 
by exhausting the vegetative powers of the plant. Vegetables also have thepow( 
of absorbing moisture from the atmosphere, and must consequently sulFer in propo ' 
tion as this is in an arid state. Those three considerations show the great impor 
ance of a vaporous atmosphere in hothouses raised by keeping the floor of tl 
house and surface of the flues continually wet/’ I 
Mr. Knight was also a great advocate for an absolutely saturated state ( 
vaporisation, that is, when high temperature was kept up ; and now, havir 
appealed to the authority of past years, we may with more propriety cite tl 
evidence of recent facts accruing under a much improved method of heating, as 
during a winter unusually sombre and of protracted severity. 
We have said that some writers have lately expressed their opinions of the ris 
that must have been incurred by those gardeners who had to depend on fire-flu 
only during the late black winter. A very few years have elapsed since there wel 
no other appliances of heat than such flues ; and winters of equal rigour ha; 
repeatedly occurred without producing any disastrous results. We happen f 
possess opportunities of comparing the progress and effects of the two methods! 
heating, carried on pretty extensively, and can therefore assert that we never sal 
a large greenhouse, filled with the finest specimens of Camellia, Epacris, Acaci}| 
and other hard- wooded species, with a liberal admission of Cyclamens, Mimiilul 
Cinerarias, and the more succulent tribes, in a higher state of health, perfect foliag 
and brilliant flowers ; and this greenhouse was heated by a fire-flue only, runniij 
abreast of the front wall, though not quite in contact with it. The aspect is eas! 
by-north, and, therefore, without sun from November to mid February. The 
facts may tend to calm the anxiety of those who are over-solicitous concerning tlj 
absence of the direct solar ray. |i 
Again, we see a beautiful crop of grapes, with noble foliage, in a stovSy heahj 
by broad, expansive, water channels, the clusters stoned and nearly ready to acqui 
colour in the second week of April, I 
A flower -house is in two compartments ; the one excited by a gutter-tank, fro 
which are continued a double course of six inch by four channels, the other, by| 
single course of the same, admitted from, and returning to, the former, throuj 
openings made in the partition wall. Now, in all these houses, wherein of courl 
there has existed a great difference in temperature, from 50^ to 73®, every plaj 
has prospered. |j 
The moisture has been considerable, in the tank department particularli 
wdierein a great number of Gardenias are, and have been, in rich verdurj 
w'hile almost every cutting of this plant has taken root, and is growing aft| 
transplantation into small pots. P 
Darkness — fog of dense character — absence of sun for weeks, may ha^ 
retarded, but they have done no injury. Even Hibiscus rosa sinensis^ you! 
plants of spring cuttings, have not lost a leaf: thus we have ample evidence, tli 
