December 6,1883. ] 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
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Royal Society at 4.30 r.M.; Linnean Society at 8 r.?j. 
Royal Botanic Society at 3.45 P.ir. 
2ND SUNDAY IN ADVENT. 
Royal Geographical Society at 8.30 P.M. 
Royal Horticultural Society, Fiuit and Floral Committees at 11 A.M. 
Society of Arts at 8 P.JI. 
FIRING AND VENTILATING. 
ESE are of no mean importance in cultural 
practice; indeed, very much depends upon the 
application of heat and air in the cultivation of 
plants under glass in relation to a successful 
or unsuccessful result, and they bear such a 
correlation to each other, especially in forcing 
operations, that the one depends greatly upon 
the other as to the method of applying them. 
Every cultivator is cognisant of the im¬ 
portance of the heat being of the required degree, and yet we 
not infrequently find less knowledge, at least less attention, 
given to the matter than is considered needful in less 
important details. There may not be any great difficulty 
in large establishments where the heating apparatus is all- 
sufficient for its work, and the water in the apparatus kept 
at a temperature little short of boiling constantly, as it then 
resolves itself into a matter of regulating the heat by the 
valves, any not required being kept in stock that can be 
drawn upon as the necessities of the several departments 
demand; but the case is very different where a boiler has to 
do the work of but one or a few compartments, and the 
stoking is dependent on those but little experienced in 
the work. I do not propose to enlarge on the art of firing, 
only to point out that it is as well worth anyone’s while to 
learn how to fire as it is to know how to attend to the 
requirements of plants in the matter of watering and venti¬ 
lating, and the knowledge acquired on the latter point is of 
equal importance as that on the former in attaining pro¬ 
ficiency in the art of gardening. 
Although everybody knows that water cannot be made 
hotter than 212°, or boiling point, without its being converted 
into steam, yet it is well to bear in mind that the pipes 
may become too cold by an overdose of fuel; then by sharp 
working of the fire they are made quite hot again to atone 
for the mistake. Such, I need not say, is not good stoking. 
In fact more harm is done by this alternate roasting and 
starving process than any other in relation with heat. It is 
not corresponding to alternating blinks of sun and a cloudy 
sky, for the sun-heat fluctuations are accompanied with 
corresponding degrees of light, whilst this is not so with 
artificial heat, consequently the temperature needed by this 
means should be as little given to fluctuate as possible. The 
art of firing is to produce a temperature corresponding to 
that accorded by Nature to different descriptions of plants 
It is vain to suppose that an artificial temperature can be 
produced superior to a natural one, yet an artificial climate 
may be produced in which plants will attain to greater excel¬ 
lence than in their native habitats; still, it is by a combination 
of conditions in addition to artificial heat that such are 
obtained, the plants not being subjected to any of the 
vicissitudes they incur in their native homes. 
In the application of artificial heat the object should be 
to diffuse it at a temperature as low as is consistent with 
attaining the desired end. If we have a greenhouse it is per¬ 
nicious to only provide so much piping that it must be kept 
at nearly 200° to exclude frost, as the heat radiating at so 
high a temperature will dry the air in the immediate proxi¬ 
mity of the pipes as to injuriously affect the plants. Sufficient 
piping to keep the temperature to the required degree without 
heating it more than to 100° would be far better. Then the 
artificial heat should always be such that the maximum 
temperature will be obtained in the daytime. Very frequently 
this is not the case, especially in cool houses. Fire heat is 
applied at night in case of a probable frost, and the tempera¬ 
ture is kept at what ? Well, I have often seen it over 50° 
at ten o’clock at night, because the expected frost has not 
come, and I have seen the same house the next day at 40°, 
with a current of air. The nights are thus turned into days, 
and vice versa. Softwooded plants soon became of a sickly 
green, and thin in texture of foliage, simply because the 
growth is made by the artificial heat in the dark. In this 
case the house should not have had the heat at night so as to 
raise it above the day temperature, and if it were needed at 
all the day should have exceeded that-at night by at least 5°, 
or, if cold and dull, it may approximate as near as possible to 
the night temperature, or 40° to 45°. 
In more highly heated houses extra heat is very often 
turned on in anticipation of a cold night. Those who do 
this know full well what it means—viz., saving themselves— 
providing for their own convenience, not that of the require¬ 
ments of the plants. If the anticipations are not realised 
the fire will have raised the temperature many degrees 
higher than it ought to have been, and injury is done which 
with a few repetitions soon becomes apparent. There is no 
remedy for this but assiduous attention and thorough ground¬ 
ing in the practice of firing. A few degrees’ lower tempera¬ 
ture during sudden depressions of the external temperature 
are not injurious, but conducive to the health of the plants, 
as it is only so much more rest given them, and that they 
can hardly have too much, provided always that it be safe. 
Then in forcing operations it sometimes is allowed to 
happen that a temperature is obtained which should never be 
tolerated. I have seen vineries at 70° at ten o’clock at night, 
when 60° was suitable, to allow of a fall to 55° by morning, 
and the pipes at the same time scarcely warm in the morn¬ 
ing. Such is not good firing, but is a certain indication of 
the stoker never making a mark in his profession. But firing 
is dirty work. I know it, having had some twenty-four to 
look after when young, and half a mile to trudge knee-deep 
in snow to some of them when only owls kept awake. Things 
have altered since then, and the duties of under gardeners 
are very much less onerous. In the matter of heat it is only 
a question of turning valves in some establishments, and in 
most no more real work is needed than in using a poker, coal 
rake, and throwing fuel into the furnace. It is essential 
that firing be understood, and this comes _ of the exercise of 
some judgment in combination with practice. 
In forcing operations sudden fluctuations of artificial 
temperatures are very baneful—in some instances fatal. 
There are a few points in connection with the application of 
fire heat in forcing that cannot well be overlooked. The 
first of these is to raise the temperature to its maximum from 
fire heat in the early part of the day, or within an hour or 
so of sunrise, and to maintain it at that until near night¬ 
fall. This will afford a long day of growth, and elaboration, 
and assimilation of the juices of the plants, and the growth 
so made will be firm and solidified, and the foliage leathery 
in texture, but it will be soft if made in a close atmosphere 
with the night temperature as high as the day. The second, 
point is that of the night temperature being kept 5° to 10° 
lower than the day. This should commence to take place 
from dusk. The lower temperature will cause a cessation of 
growth, induce rest, and prevent that weak condition of the 
growth and thinness of the foliage only too frequently seen 
in forcing. A fall of 5° from dusk to nine or ten o’clock, and 
another fall of 5° by the time the house is entered in the 
morning, will approximate very nearly to a correct state of 
things. Then, as before stated, the heat shoukl not be 
radiated at a high temperature, for where the pipes are 
