74 
ON THE BOMBAX CEIBA. 
respectively. This can be filled with water in ten minutes, and as speedily drawn off by 
a plug into the house drain. A line of six-inch piping runs from one end to the other at 
front, under the centre of the front shelf; and another similar line of piping under the centre 
of the back stage. A portion of this line is composed, at intervals, of Burbidge and Healy’s 
tank, with moveable lids, the rest connecting them round piping, as before observed. 
Now, as to ventilation. The roof is glazed with the sheet glass, in large panes, 
about seven inches wide, by nearly two feet in length, and it is fixed. Clappers, or 
drop flaps, capable of graduation, are placed in the back wall, under alternate lights, close 
to the wall-plate ; these are eighteen inches long by twelve inches in depth. The front 
sashes are nearly a yard in depth, and one-half of these drop or slide down three inches, 
when necessary, after the manner of ordinary house sashes ; the other half open outwards 
from their lower end, with a nicely graduated iron rod. The principal points of ingress 
for the cold and fresh air are at the very lowest level at front : sliding ventilators are 
placed along the front wall, and these open immediately on the hot- water piping, which 
rests on the sunken panel before described as being generally filled with water. 
By this arrangement my intention was to give a specific direction to the warmed and 
moistened air, without being compelled to suffer it to escape by the back ventilator, which, 
in the growing season, are frequently too great a drain on the atmospheric moisture. The 
working of these things turns out as I had anticipated ; for, by drawing down the front drop- 
sashes, and at the same time opening the sliding ventilators, at the low level at front, 
a rotary kind of circulation immediately takes place ; a constant current of warm moist air 
passes over the floor of the house, under the shelves and stages, rises up the back wall, 
and through the bars of the stage, and returns down the roof to the apertures at the top 
of the drop-sash in front, where, under certain conditions of atmosphere, a continual 
current of moist air may be seen pouring forth. 
This house has a shading on a roller — the shading material from Mr. Yexley of Merton, 
as before observed, and this I have used as a night covering through the winter, making a 
point of maintaining a very moderate fire through the night ; seeking a night temperature 
hitherto of 55° to 60° — a great proportion of the Orchids being the Mexican and 
Guatemala kinds. 
I think the plan of sunken panels beneath the stages and shelves good ; and it would 
be well, according to my opinion, so to arrange the piping, as that one advancApipe above 
the floor-level should be made, after traversing the house lengthwise, to discharge itself 
into two return-pipes, both lying on the bottom of the sunken panel, and surrounded with 
water at will, as before described — a constant supply of mild vapour being far preferable 
to fitful applications of hot steam ; especially if a constant motion is maintained in the 
atmosphere. 
ON THE BOMBAX CEIBA, OB COMMON SILK-COTTON TBEE OF SOUTH 
AMEBICA AND THE WEST INDIES. 
The Silk Cotton Tree 
( Bombcix Ceiba) is a native of South America and the West 
Indies, whence it was introduced to this country about two hundred years ago. As the 
tree, however, does not flower until it has attained a large size, no specimen that we are 
aware of has bloomed in this country, except the one growing in Chatsworth large con- 
servatory, which produced only a single flower in November, 1848. 
In the extensive forests where this species is a native, it grows to a large size, and 
forms a noble wide spreading tree, 130 or 150 feet in height; the trunk and branches 
are thickly covered with strong sharp prickles. The bark is dark brown. Leaves alternate, 
palmate, deciduous ; leaflets five, occasionally seven. Petioles long. Flowers large, three 
inches or more in diameter, of a dull yellow, striped and tinged with dull red, produced 
singly at the extremities of the young leafless branches. Calyx naked, campanulate, 
truncately five-toothed. Petals five, connected at the base with the column of the 
