12 THE FORCING GARDEN. 
No early vinery should contain too much glass. 
When I say ‘too much,’ I mean that there should be 
none on the cold sides. There is nothing like a good 
dry brick wall for the back of an early vinery, with but 
little or no glass at the ends. A house constructed on 
my plan, i.e. at the angle above named, will be abund- 
antly light enough without any more glass than what 
the roof contains, and will be better adapted for main- 
taining the necessary heat at a less cost. 3 
In constructing a back wall, it will be a great ad- 
vantage in every way to build it according to my 
method, that is, hollow. A wall constructed on this plan, 
60 feet long, 12 feet high, and 9 inches thick, will 
take about 5,360 bricks; while one of the same dimen- 
sions built with solid work, as is usually done, will take 
7,930 or thereabouts. Here then is a difference of 
2,570 bricks in the first place, and then there isa 
saving of at least 1/. in mason’s and mason’s labourer s 
wages and mortar. Nor is this all, for a wall so con- 
structed is much drier, and therefore of necessity much 
warmer; the wall is full of chambers of heated air, 
which continue to give out their contents by night into 
the house, which is an immense advantage in early 
work, as by this means a better result is obtained than 
by a fire-heated flue. In virtue of such a wall, tke 
angle of roof, and the construction of an apparatus 
like that shown in fig. 6, I may challenge all others, 
that is, supposing the roof to be double-glazed on my 
plan, and having the ‘ border protector.’ 
