CULTURE OF ROSES IN POTS. 
131 
portion of moisture be required by the vegetable structure; fre¬ 
quent syringings also become necessary, not less to remove and 
dislodge insects than to clean away from the breathing appa¬ 
ratus of the plants any incumbrance which may have been de¬ 
posited on it, and thus tend to impair its action ; the moisture 
of the atmosphere should be maintained by sprinkling the heated 
pipes frequently, and by the aid of “ evaporating troughs” placed 
on them. The application of moisture at the root should be suf¬ 
ficiently bountiful to render soluble the food contained in the 
soil, and thus suitable to be taken up by the spongeolesor feed¬ 
ing apparatus of the plants ; but it should, at the same time, be 
sufficiently limited to prevent the medium in which that food is 
embodied, from becoming soured or soddened. 
Provided that attention is paid to keep the atmosphere free 
of extraneous impurities, it cannot be maintained in too calm a 
state at the time of the development of the leaf buds and during 
the earlier stages of growth ; the young shoots of roses are very 
succulent and, together with the blossoms, are very delicate and 
tender, and are therefore liable to become seriously injured by 
exposure to a current of cold air; this,injury should be parti¬ 
cularly guarded against and avoided, by keeping the house 
closed as far as may be practicable. Mr. Knight has somewhere 
stated his belief, founded on his own observations, that it is by 
no means necessary to change the body of air in a hothouse, by 
admitting cold air largely by opening the sashes, provided the 
internal atmosphere was kept free from impurities which might 
arise from the soil or other causes ; a sufficient change of air, he 
believed, would take place in a house kept closed, at least when 
any considerable difference existed between the external and in¬ 
ternal temperature, through the various openings and creaks, 
which, though scarcely discernible, are known to exist nume¬ 
rously enough in all plant structures. This opinion is strongly 
confirmed by the success which has attended a recent adaptation 
of the principle by Mr. Ward ; and perhaps one of Mr. Ward’s 
cases might be turned to a less appropriate or pleasing use than 
to the sheltering of a “ little forest of roses.” To this I may 
add the testimony of Mr. Rivers (who is no mean authority on 
matters connected with roses), and he has very lately stated his 
conviction that the healthiness , the fragrance, and the beauty 
of his partially-forced roses, resulted more particularly from 
