ches deep; that is, the depth of one
board.

In making up the beds, bring in the manure and shake it up loosely and
spread it evenly over the bed, beating it down firmly with the back of
the fork as you go along, and continue in this way until the desired
depth is attained. If it is a floor bed and there is no impediment, as
a shelf overhead, tread the manure down firmly and evenly; if the manure
is fairly dry and in good condition it will be pretty firm and still
springy, but if it is too moist and poorly prepared treading will pack
it together like wet rotten dung.

Now pierce a hole in the bed and insert a thermometer. There are
"ground" or "bottom-heat" thermometers, as gardeners call them, for this
purpose, but any common thermometer will do well enough; and after two
or three days examine this thermometer daily to see what is the
temperature of the manure in the bed. In roomy or airy structures or
where only a small bed has been made it may, in the meantime, be left in
this condition. But in a tight cellar I find that the warm moisture
arising from the bed condenses in the atmosphere and settles on the top
of the manure, making it perfectly wet. In order to counteract this, as
soon as the bed is made up I spread some straw or hay over it loosely;
the moisture settles on the covering and does not reach through to the
manure. Beware of overcovering, as such induces overheating inside the
bed. At spawning time remove this covering. The bed will then have
become so cool (80 deg. or 90 deg.) that there is very little evaporation from
it, consequently little danger of surface-wetting.

=The Proper Temperature.=--This, in mushroom beds, depends upon the
materials of which they are composed, their thickness, how they are
built, the situation they are in, and other circumstances. If the manure
was good and fresh to begin with, carefully prepared and used as soon as
ready, the bed in a few days will warm up to 125 deg., or a little more or
less, and this is very good. My best beds have always shown a maximum
heat of between 120 deg. and 125 deg.. Had the manure been used a few days too
soon the heat would rise higher, perhaps to 135 deg., but this is too warm;
in this case I would fork over the surface of the bed a few inches deep
to let the heat escape, and after a couple of days compact the bed
again. Boring holes all over the surface of the beds with a crowbar is
the common way of reducing a too high temperature, and w