mine are not wet from the dripping
water. The most extensive one which I have visited is located at Akron,
New York, and is operated by the New York Mushroom Company. In a single
abandoned cement mine there are 12 to 15 acres of available space; about
3 to 5 acres of this area are used in the operations of the culture and
handling of materials. The dry portions of the mine are selected, and
flat beds are made upon the bottom rock, with the use of hemlock
boards, making the beds usually 16 feet long by 4 feet wide, the boards
being 10 inches wide. In this case, the beds, after soiling or
finishing, are 9 inches deep, the material resting directly upon the
rock, the boards being used only to hold the material on the edges in
position. Figures 223 and 224 illustrate the position of the beds and
their relation to each other, as well as showing the general structural
features of the mine. The pillars of rock are those which were left at
the time of mining, as supports for the rock roof above, while
additional wood props are used in places. In this mine all of the beds
are constructed upon a single plan.

[Illustration: FIGURE 225.--View in Wheatland cave, showing ridge beds,
and one flat bed. Copyright.]

At another place, Wheatland, New York, where the Wheatland Cave
Mushrooms are grown, beds of two different styles are used, the flat
beds supported by boards as described in the previous case, and the
ridge beds, where the material, without any lateral support, is arranged
in parallel ridges as shown in Fig. 225. This is the method largely, if
not wholly employed in the celebrated mushroom caves at Paris, and is
also used in some cases in the outdoor cultivation of mushrooms. As to
the advantage of one system of bed over the other, one must consider the
conditions involved. Some believe a larger crop of mushrooms is obtained
where there is an opportunity, as in the ridge beds, for the mushrooms
to appear on the sides as well as on the upper surface of the beds. In
the flat beds the mushrooms can appear only at the upper surface,
though occasionally single ones crop out in the crevice between the side
board and the rock below.

[Illustration: FIGURE 226.--Single mushroom house (Wm. Swayne, Kennett
Square, Pa.), "curing" shed at left. This house is heated in connection
with other hothouses.]

Probably at Paris, and perhaps also at some other places where the
system of ridge beds is used, the question of the cost of the lu