242. _b b b_ are fifteen posts, nine feet high, and six inches through at the bottom, without much tapering towards the top. These posts stand about two feet apart, reckoning from centre of post to centre of post, which leaves between each two a space of eighteen inches, _c c c c_ are fifty-four posts, five feet high, and five inches through at the bottom, without much tapering towards the top. These posts stand about two feet apart, from centre of post to centre of post, which leaves between each two a space of nineteen inches. The space between these two rows of posts is four feet 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_]