ut instead boxed
off about two inches from the walls, so as to remove the beds from the
chilling touch of the wall in winter. Economy may suggest the
advisability of high mushroom houses, so that one may be able to build
one shelf above another, until the shelves are two, three, or four deep.
But this is a mistake. The artificial heat required to maintain a
temperature of 55 deg. in midwinter in a house built high above ground would
be too parching and unsteady for the good of the mushrooms; besides, a
second shelf is inconvenient enough, and when it comes to a third or a
fourth the inconvenience would be too great, and overreach any advantage
hoped for in economy of space. An unheated mushroom house must be
regarded as a shed, and treated similarly, as described in the following
chapter.

In large, well appointed, private gardens, a mushroom house is
considered an almost indispensable adjunct to the glasshouse
establishment, and is generally built against the north-facing wall of a
greenhouse. In this way it gets the benefit of the warm wall, and may be
easily heated by introducing one or two hot-water pipes from the
greenhouse system; besides, in winter the house may be entered from the
glass house or adjacent shed, and in this way be exempted from the
inclement breath of the frosty air that would be admitted in opening the
outside door.

[Illustration: FIG. 10. INTERIOR VIEW OF MR. S. HENSHAW'S MUSHROOM
HOUSE.]

=Mr. Samuel Henshaw's Mushroom House.=--Mr. Henshaw has raised
mushrooms several years at his place on Staten Island. His mushroom
house is nine feet wide and sixty feet long. One side is a brick wall
and the other is double boarded. The roof is of tin, in which there are
three sashes each two by five feet, supplying ample light. At each end
is a door giving convenient access to the interior, for carrying in and
removing material without disturbing the bearing beds. In winter the
roof is covered with a coating of salt hay, to preserve an equable
temperature and prevent the moisture from condensing on the ceiling and
falling in drops on the beds. The floor is of earth, which, when well
drained, he thinks preferable to either brick or lumber. The floor is
entirely covered with beds, no shelves or walks being used. This makes
it necessary to step on the beds, but as no covering is employed it is
always easy to avoid stepping on the clusters of young mushrooms, and so
long as they are left uninjured the bed i