788 THE GARDENERS 
CHRONICLE. 
[Nov. 11, 
circulation. A rejection of the or 
shifts is here decisive of the applicability of small growth 
to comparatively large masses of soil, if, in the first in- 
Stance, adapted to the ultimate object, by arrangement, 
exposure to intense agency, &c. 
The risk attendant vpon ‘a compression ” of the roots 
may be adduced as an additional evidence of the evils con- 
nected with repeated shiftings. If a slight « compression” 
of the roots tend to ‘interrupt’ the circulation of fluid 
from the roots, what must be the effect of the whole 
inward resisting medium of smaller on larger pots? If 
‘compression ” interferes injuriously with ultimate effect, 
then allinverted growth must be subversive of the vital 
energy of plants. 
———_—_—. 
FORCING THE NEAPOLITAN VIOLET. 
Tux subject will divide itself under the following heads : 
— Propagation of Plants; Cultivation or Preparation of 
do.; Preparation of the Frame or Pit ; and Subsequent 
Management. 
I.—Propagation of Plants.—Some cultivators obtain 
their forcing-plants from the old forced plants of the pre- 
vious season this is not the best plan, as the plants have 
become somewhat exhausted, and are apt to produce long- 
jointed runners. My plan is this :—When I plant my 
pit or frame for forcing, I plant the remainder which are 
to spare in a bed of rich soil, with a view to providing 
runners for the succeeding year. In the end of February, 
old tan is riddled through them ; and on this, by the 
middle of May, the runners have so luxuriated that they 
are fit for removing to prepared beds, to undergo the cul- 
tivation necessary, now prepare as many beds as are 
requisite in an open and warm part of the kitchen- garden ; 
the beds receive a good dressing of equal parts heath- 
soil, leaf-mould, and strong yellow loam, which is well 
blended with the bed; no dung is used at this stage of 
the process, as my object is to obtain an early, stout, and 
firm plant, but not a gross one. The plants are set out 
afoot apart each way, and throughout the summer ar 
kept free of weeds and runners, and freely watered through 
the months of May, June, and July, if necessary. In 
August I suffer them to become rather dry, which induces 
asort of rest, and enables the plant to concentrate its 
energies for the production of blossom ; this temporary 
cessation of their fitful luxuriance I find of considerable 
importance, as the plants by this time, if they have taken 
well to the soil, are generally somewhat rampant, and, as 
a necessary consequence, spawn forth a superfluity of 
long-jointed runners; now there is no great harm, s0 far, 
if their pride be timely arrested. 
If the cultivation above described be systematically 
pursued, the plants will be fit to remove to their winter- 
quarters by the middle of September. % 
The grand desideratum now is a pit or frame with 
bottom-heat, This last is a prime secret in the affairs 
Most cultivators think they have done ample justice to 
this lovely winter-flower when they have planted them on 
the remains of an old Melon-bed, afterwards depending 
on a sort of winter-forcing by hot linings ; this, however, 
in my opinion, is mistaking in some degree the habits and 
capacities of the plant. The plant, it is well known, is 
impatient of confined damps, and would rather be on an 
old hedge-back than in the finest pit extant; now, if the 
plants are grown late, and the ladies require them in 
bloom by November, there is no alternative but this 
attempt at forcing them, which I most strenuously repu- 
diate. 1 merely contend that by an early application of 
bottom-heat through part of September and October, in 
conjunction with the cultivation as above, there will be 
little necessity for hot linings, or, in fact, for any renewal 
of artificial heat ; the only remaining points being to keep 
out the frost—give air most freely—and shut up warm 
early when sunshine occurs. However, to the point. 
1 pretend not here to dictate the mode of acquiring 
bottom-heat ; and I have no doubts whatever on my mind 
that we are not merely on the eve of a revolution in these 
things, but actually at the day-spring itself. The bottom: 
heat I advise is to 80 degs. as near as may be, and if 
this can be ensured steadily, or rather slowly declining 
for a month or six weeks, all is right. 
The plants should be placed in the pit, or bed, about nine 
inches apart each way, and should be removed with good 
balls of earth. My plan of planting is this:—After 
securing the necessary bottom-heat, I place a layer of old 
rotten hotbed-manure, three inches thick, on the ferment- 
ing matter ; the surface of this last is brought to within 
10 inches of the lights back and front, aud of course 
nearly parallel to the roof. The balls are placed in the 
manure, and filled up as the planter proceeds, with the 
following compost, pressed firmly around the plants :— 
Strong maiden yellow loam Ni . ; . + 4 parts 
Old leaf-soil . . . . . . . . . 
Rotten horse and cow-dung, thoroughly decomposed 9 
Sandy heath-soil , . . . . . . . 3 
Inimediately they are finished I give them three or four 
gentle waterings with tepid water, in rapid succession— 
in fact, all within two days, and Trepeat the same process 
about the middle of October; after which period they 
never receive a drop until the beginning of February. 
The subsequent management now proceeds entirely on 
the habits of the plant, viz., impatience of frost and 
humidity of atmosphere, to which I might add an equal 
impatience of dry heat, as produced by flues or pipes, 
although I am of opinion that a small hot-water pipe in 
the pit would be of advantage occasionally, if the fire 
were worked with much caution and with a continual 
respect to the habits of the plant. 
The routine of business through the winter is to cover 
up well at night with mats, and in severer weather, hay 
and straw besides, and to be equally particular to get a 
A COMMENTARY ON CERTAIN PASSAGES IN 
THE PHYSIOLOGICAL WRITINGS OF THE 
LATE ANDREW THOMAS KNIGHT. 
BY W. Woop. 
(Concluded from page 771.) 
No. 1V.—On tue Currivarion or THE Prnz-Appie. 
—‘‘ The temperature of the house raised by means of 
solar heat from 95° to 105°, sometimes to 110°, no air 
being given till the temperature exceeded 95°, The com- 
post of thin green turf chopped very small, and pressed 
very closely whilst wet ; a circular piece of the same ma- 
terial being inserted to occupy the bottom of each pot: 
having found this substance most efficacious for draining 
&c., and subsequently of facilitating the removal of a plant 
from one pot to another without loss of roots. The pots 
elevated upon brick piers near the glass.”— Horticultural 
Transactions, vol. iv. 
Remarks.—This paper bespeaks an advance in the 
principles of cultivation, and tends to illustrate the first 
principles of Horticulture. There is the application of 
higher agencies, which, in some measure, may be regarded 
as a new power, subservient to the highest possible effects 
in cultivation ; and, in the * chopped green turf, is given 
a texture and mechanical arrangement, adapted to the 
power of the agency applied, and the attainment of a 
uniform circulation of moisture.” This paper may also be 
considered a full illustration of the following opinion given 
at p. 112 of Paxton’s Magazine, viz. i—** Atmospheric 
and solar influence should be so modified as to balance the 
power of absorption to which plants are exposed, &c.”” 
There are also valuable inferences to be drawn from the 
use of chopped turf, as a “substratum” or drainage ; 
perhaps a perfect system of cultivation will include the 
complete subserviency of the mechanical to the assimiln- 
tive process in the economy of vegetation. The safe 
“removal of plants from one pot to another, without loss 
of roots,” appears to be a dim recognition of that “ Prin- 
ciple of Horticulture” by which an accumulative system 
of cultivation must either stand or fall, viz., that ‘* for the 
maintenance of a plant in health, it is indispensable that 
the supply of fluid by the roots should be continued and 
uninterrupted ” (Principles, 32). Here it may be observed, 
that until it can be proved that the removal of plants from 
One pot to another does, in no wise, affect them injuriously 
under the same circumstances, the principle now quoted 
must for ever decide the question of expediency. The 
removal of plants without loss of roots is certainly desir- 
able ; but the question again recurs—Can they be removed 
at all without sustaining a loss of that Sunctional power, 
by the continued uniform reciprocal action of which the 
“supply of fluid by the roots” can alone “be continuous 
and uninterrupted >” Every hour’s experience denies the 
possibility of this. 
0. V.—Ow tue Curtivation or tHE CocKscomn, 
—‘‘ Treatment similar to the Pine-apple, having a similar 
object in view. | A single flower-stalk of great strength is 
requisite, the protrusion of which should be retarded as 
long as possible, consistently with the rapid growth of the 
plants. Compost, nutritive as possible, and stimulatory ; 
of unfermented horse-dung, fresh, burnt turf, decayed 
leaves, Two parts green turf, the latter being in lumps 
of about an inch in diameter, to keep the mass so hollow 
for escape of water (uniform circulation) and the air to 
enter. Plants put very young (small) into pots 4 inches 
diameter and 3 inches deep; as soon as the roots had 
reached the sides, in no degree matted, they were trans. 
ferred to pots of a foot in diameter and 9 inches deep. 
Particular attention paid to the roots, having reason to 
think that the compression of them in the pot has 
under all circumstances, a tendency to accelerate the 
bloom. Under this treatment the plants became large 
and strong before they manifested a disposition to blossom. 
Plants Placed within a few inches of the glass, and 
subject to similar heat as the Pine-apple plants.””—Hort, 
Trans., Nov, 4, 0. 
Remarks.—The above instance of cultivation may be 
considered a-full pecegaition of a progressive and accumu- 
lative system: ‘of »eul tivation, illustrating a rule to be 
observed in cultivation aie 
should ntecedent to. 
° 
erally, that maturity of growth 
rf A ore temr 8 with, a deve- 
lopment of bloom. It also points out the necessity of a 
ppoe real arrangement of’ soil being equal to a uniform 
i), 
ATOINOHHD 
SMANGuyvo 
nary mode of repeated 
— ————ae 
circulation of dry air on every little occasion, never letting 
an opportunity slip, 
The plant is naturally fond of a soil somewhat rich, 
and for this reason I place the balls immediately im 
contact with the manures. As, however, manures ares 
as I suppose, rather absorbent of atmospheric moisture 
use a considerable portion of heath-soil in the frame 
mixture, and I find that theory and practice perfectly 
agree as to this material, for when once dry on the surfaces 
it keeps dry, and I believe acts also in some degree as al 
antiseptic. ’ 
Violets are generally much annoyed with slugs, which 
deface the flowers. When such is the case I sprinkle the 
bed all over with a good coat of coarse river-sand, in @ 
dry state, and when the plants are perfectly dry: this 1 
with me an infallible preventive. 1 have grown Violets 
for 23 years, and every winter I can find some slight 
room for improvement. ‘Those, however, who strictly 
follow the principles here laid down, will seldom want 
Violets from the end of October to the end of April.— 
Robert Errington, Oulton Park 
ON THE ATMOSPHERE OF HOTHOUSES. 
(Continued from page 772.); 
Aurnuoucu I may have incidentally verged into the 
subject of bottom-heat, I may be excused, inasmuch as it 
is intimately blended with my general topic, in the tank 
system, for that process is made to affect both soil and 
atmosphere at once. 
water-pipes can be permitted or withheld at pleasure ; by 
this means a complete control is exercised over both the 
bottom-heat and atmospheric temperature, so that each 
can be regulated to the nicety of a degree. This is pro- 
bably the most complete apparatus for heating a hothouse 
requiring bottom-heat which can be employed. 
Light.—Under this head I shall be very brief, When 
one considers the intense flow of light many of our tender 
plants must receive in their native regions, and that the 
glass covering of our hothouses always, under the most 
favourable circumstances, throws off a portion of the light 
reaching its surface, the necessity for constructing these 
as lightsome as possible must be apparent. MM. Bouguer, 
Lambert, and others, determined by experiment that the 
nearer the perpendicular light falls on the surface of glassy 
the more of that light passes through. The sun alters its 
position least in the same time when on the meridian, or 
rather about it, that is, about noon. Moreover plants 
require most light when in the vigour of their growth. 
These three facts combined will lead us to the proper slope 
of a house for plants we are cultivating, giving it an in- 
clination at right angles to the sun’s rays at noon at that 
season of the year we wish for most light. The technical 
formula will, for this angle, be— ‘ 
pmedatiiude of the plate! — inva declination otairereuencii 
Thus, if we take London as an example, whose latitude is 
1° 3I’N.; andifa slope is required for the greatest light 
at midsummer, the sun’s declination at that time is 
23° 29’ N., which is subtracted from the latitude 51°31/Ny 
both being of one name North, and leaves 28° 2’ ag the 
angle or slope of the roof with the horizontal, for a mid- 
summer house at the latitude of London. ‘This is rather 
a flat roof I acknowledge, and not so easily kept 
tight as a steeper slope; but 30° will do very well when 
properly executed, as I have the experience of in oné 
of my own. In steeper slopes than the above there 
are two periods in the year when the greatest amount of 
light is admitted by them. If we take a slope of 450— 
which is, in fact, a very common one for Vineries—the 
sun’s rays enter it equally and with greatest freedom about 
the 7th of April and 7th of September, periods which may 
be taken advantage of accordingly. Curvilineal roofs have 
been constructed for the purpose of opposing at all times 
a portion of their surface perpendicular to the sun’s rays, 
and at the same time, being of iron, to present as little 
opaque surface as possible. For conservatories these are 
unrivalled, both for elegance of appearance, and a regular 
supply of light at all seasons of the year ; but it is evident 
they cannot give so full a flood of light as straight roofs 
can do, at a particular season, when that may be desirable ; 
and it is, therefore, unlikely that they will ever supersede 
the ordinary roof in the common purposes of gardening. 
Having said thus much on the soutl c 
* T perceive I ated in Burbidge an ly’ 
date 21st October. See advertisement in Chronicle, 
