390 
LANDSCAPE GARDENING. 
eighth of an inch, while it would require to be one-fourth 
of an inch, were the panes of the usual size. On the front 
and sides, the sashes may be handsome, and filled in with 
the best glass; even plate glass has been used in many 
cases to our knowledge here. 
In the second place, some thorough provision must 
be made for warming the conservatory ; and it is by far the 
best mode to have the apparatus for this purpose entirely 
independent of the dwelling house ; that is (though the 
furnace may be in the basement), the flues and fire should 
be intended to heat the conservatory alone ; for although 
a conservatory may, if small, be heated by the same fire 
which heats the kitchen or one of the living rooms, it is a 
much less efficient mode of attaining this object, and 
renders the conservatory more or less liable at all times 
to be too hot or too cold. 
The common square flue, the sides built of bricks, and 
the top and bottom of tiles manufactured for that purpose, 
is one of the oldest, most simple, and least expensive 
methods of heating in use. Latterly, its place has been 
supplied by hot water circulated in large tubes of three 
or four inches in diameter from an open boiler, and by 
Perkins’s mode as it is called, which employs small pipes 
of an inch in diameter, hermetically sealed. Economy 
of fuel and in the time requisite in attendance, are the 
chief merits of the hot water systems, which, however, 
have the great additional advantage of affording a more 
moist and genial temperature. 
In a green-house, the flues, or hot water pipes, may be 
concealed under the stage. In conservatories they should 
by all means be placed out of sight also. To effect this, 
they are generally conducted into a narrow, hollow 
