eet in width, and, as will be presently seen, is to contain _a
wall of straw_.

243. _e_ is a passage through this wall; _d_ is the outside door of the
passage; _f_ is the inside door; and the inner circle, of which _a_ is the
centre, is the place in which the ice is to be deposited.

244. Well, then, we have now got _the posts_ up; and, before we talk of
the _roof_ of the house, or of the _bed_ for the ice, it will be best to
speak about the making of the _wall_. It is to be made of _straw_,
wheat-straw, or rye-straw, with no rubbish in it, and made very smooth by
the hand as it is put in. You lay it _in very closely_ and very smoothly,
so that if the wall were cut across, as at _g g_, in FIG. 2 (which FIG.
2 represents _the whole building cut down through the middle_, omitting
the centre post,) the ends of the straws would present a compact face as
they do after a cut of a chaff-cutter. But there requires something _to
keep the straw from bulging out between the posts_. Little stakes as big
as your _wrist_ will answer this purpose. Drive them into the ground, and
fasten, at top, to the _plates_, of which I am now to speak. The plates
are pieces of wood which go all round both the circles, and are _nailed on
upon the tops of the posts_. Their main business is to receive and sustain
the _lower ends of the rafters_, as at _m m_ and _n n_ in FIG. 2. But to
the plates also the _stakes_ just mentioned must be fastened at top. Thus,
then, there will be this space of four feet wide, having, on each side of
it, a row of posts and stakes, not more than about six inches from each
other, to hold up, and to keep in its place, this wall of straw.

[Illustration: _Fig. 1_, _Fig. 2_, _Fig. 3_]

245. Next come the _rafters_, as from _s_ to _n_, FIG. 2. Carpenters best
know what is the _number_ and what the _size_ of the rafters; but from _s_
to _m_ there need be only about half as many as from _m_ to _n_. However,
carpenters know all about this. It is their every-day work. The roof is
forty-five _degrees pitch_, as the carpenters call it. If it were even
_sharper_, it would be none the worse. There will be about _thirty_ ends
of rafters to lodge on the plate, as at _m_; and these cannot _all_ be
fastened to the top of the centre-post rising up from _a_; but carpenters
know how to manage this matter, so as to make all strong and safe. The
_plate_ which goes along on the tops of the row of posts, _b b b_, must,
of course, be put o