1870. ] 
THE VENTILATION OF HOTHOUSES. 
227 
leaved female may be seen full of red berries. There may be those who do not 
credit the opinion that the Crambe maritima, or Seakale is the head of the 
Cabbage tribe, but who yet readily believe that wild plants can be reclaimed or 
changed by higher culture, contrary to what I have now advanced. Therefore, I 
further observe that if a Prunus Cerasus were planted out amongst trees of Prunus 
Avium, it would not degenerate or become changed into the latter, for the virtue 
of the rind of the bark forbids it. Indeed, the bark of plants may be said to be 
the truthful keeper of the peculiar virtues they inherit from seed; and upon this 
fact depends the rearing of plants by cuttings, buds, and grafts true to their kinds; 
while those raised from seed often fail to keep true.—J. Wighton, Cossey Park. 
THE VENTILATION OF HOTHOUSES. 
®fHAT a stagnant atmosphere in hothouses is inimical to the well-being of 
plants, there can be no question. Abundant testimony might be adduced 
to prove that in ill-ventilated hothouses not only are etiolated growth and 
thin sickly foliage the rule, but also that red spider and other insects 
are more difficult to keep under than when abundant ventilation is at the 
gardener’s command—the insects, a consequence or concomitant of the want of 
vigour in the plants, and the want of vigour and stamina in the plants a con¬ 
sequence of lack of the life-giving properties contained in the free air. The cry 
raised some years ago by an eminent horticulturist on behalf of plants confined 
in forcing-houses, “ Give me air or I shall dieV' was no vain appeal, and, doubt¬ 
less, has had a beneficial effect, by directing the attention of builders and 
gardeners to the importance of the subject, and thus securing the provision of 
more openings for letting in, or, more correctly, letting through the air. 
But it is well known to cultivators of tropical plants and of forced fruits, 
that something more is wanted than the means of allowing a blast to blow 
through the forcing-house, as plants under tropical treatment can no more bear the 
direct action of cutting easterly or other cold winds which the ordinary ventilators 
admit, than an Asiatic can endure with impunity the chill air of a northern 
climate. Ingenuity has been busy in devising the means for letting-in and 
letting-out sufficient volumes of air to and from our hothouses ; and many, of 
the plans in use are entitled to little more praise than is conveyed in the words 
they are ingenious.” At length, however, a plan has been brought before the 
gardening world worthy of far higher commendation, and which if it does not 
supply all that the cultivator can wish for, goes a long way towards doing so. 
We allude to Mr. Ormson’s new system of warming and airing hothouses, a 
model of which was exhibited at Oxford, at the Eoyal Horticultural Society’s 
show, and which the accompanying engraving will the better enable’ the reader 
to understand. 
By means of this novel system, a continuous supply of air, deprived of its 
chilling properties, may at all times be uninterrupted!}^ supplied to a forcing-house. 
