THE CULTURE OF ROSES UNDER GLASS. 
125 
apply to a cool house — that is, one in which Eoses are not 
intended to he forced. The depth of the top ventilators should 
be about 2 feet. 
The sills require to be 4 inches wide by 3 inches thick, 
bevelled to 2 inches on the inside. The object of this is to 
prevent water remaining on the sill to rot it. The ridge should 
be 9 inches deep by 1^ inch thick, supported by two iron 
standards up the centre of the house, with bevelled coping over 
it grooved on the under side. There may be a door at each end. 
If only one be required it should be at the south end. If there 
be two doors it is a matter of the greatest importance that both 
should not be allowed to remain open at the same time. 
The woodwork should all be painted two coats, with the best 
paint, before the house is put together, and one coat after the 
completion of the structure. The glass used for the roof should 
be that known as best 21-oz. English, free from bhsters, which 
can be obtained in sheets of any size ; but perhaps the best for the 
purpose is 15 inches long by 12 inches wide, and no putty should 
be used on the top of the glass. If larger sheets of glass are 
used there will be considerable risk of breakages from hail-storms 
and gales of wind. 
As one of the most important adjuncts to the successful 
cultivation of Eoses planted in the ground under glass is ventila- 
tion, it is necessary that I should here describe the construction 
of the roof. In a house of the dimensions suggested there should 
be on each side six sashes or lights — temporary fixtures, that is 
— securely fastened, but portable. Above these will be the six 
top ventilators on both sides, hung from the ridge on shifting 
butts, rendering these also portable. Either ventilating gear 
may be employed for the purpose of opening and closing them, 
or tlie ordinary iron " set open," as the will of the builder may 
dictate. It will thus be seen that the whole of the glass roof can 
be removed if desired (excepting the principal rafters which 
support the lights or sashes, of which there should be five on 
either side, nailed to the sill and the ridge), and when Eoses are 
planted in the ground it is most important that the roof should 
be removed about the middle of June, when indoor Eoses are 
superseded by those from the open ground, in order that the 
plants may rest and ripen ready for the next season's work. But 
it must be understood that before the glass roof is taken clean 
