Circular House for Forcing Vines. 
3U 
visions would annually bring eight hundred bunches, or thereabouts. 
Pots of Vines, Peaches, or Strawberries, might be introduced at dif- 
ferent seasons. This house should have a hot air chamber, [fig. 43] 
(a) which should be sunk sufficiently below the level of the ground (6 b) 
to admit a person to do 
repairs at the flues, &c., 
whenever it was required. 
For this purpose it would 
be necessary to have a door 
against the fire place. No 
more than one fire would 
be required to work the 
house at all seasons: the 
flue (c c) would run round 
the chamber, and the heat 
might be admitted into the 
house by holes made in the 
floor of each division. The 
floor might be supported 
by perforated walls, or by 
cast-iron bearers. I think chambering is the best method yet invented, 
being the safest and least expensive, as it regards the consumption of 
fuel. If it was objectionable to have the chimney in the centre of the 
house the flue migiit be made to terminate at some wall near, or in a 
shrubbery ; and to prevent the escape of the heat, when the fire was not 
at work, it would be necessary to fix a damper outside, for if a body of 
heat was confined in the chamber, constant fire would not be required. 
T!ie roof itself should be supported by a pillar in the centre, formed 
into a cylinder [d] left open at the top, and to prevent the rain from fall- 
ing in, a cap might be fixed over it. Two ventilators might be made in 
this cylinder; the upper one, {e) to let out the hot air, as I should not 
recommend the sashes on the roof to slide; and the lower one, (/) to 
let in cold air, which might also be admitted through each partition, 
when required. Whenever it was thought necessary to steam the house, 
the flues should have a quantity of water thrown on them, and for the 
purpose of retaining it, it-would be better if the covering of the flues was 
a little scooped out, so as to allow a small quantity of water to remain on 
the top ; — this would give up a constant moisture as long as required. 
The front of the house should not be less than six feet high; two feet 
of which, should be brick-work, and the remainder, glass. 
* I am, Gentlemen, 
Yours, &c. 
.Ao«mgr/m»M, cA'o?'. 12, 1831. J. Haythorn. 
