Nothing adds more to the outward expression of a dwelling, than the style of its chimneys. We have just shown that independent chimney tops pass off their smoke more perfectly, than when only partitioned inside to the common point of outlet. Aside from the architectural beauty which a group of chimney flues adds to the building, we have seen that they are really useful, beyond the formal, square-sided piles so common throughout the country. They denote good cheer, social firesides, and a generous hospitality within--features which should always mark the country dwelling; and more particularly that of the farmer. The style and arrangement of these chimney groups may be various, as comporting with the design of the house itself; and any good architect can arrange them as fitted to such design. Our illustrations will show them of different kinds, which are generally cheap in construction, and simple, yet expressive in their arrangement. PRELIMINARY TO OUR DESIGNS. We have discussed with tolerable fullness, the chief subjects connected with farm buildings--sufficiently so, we trust, to make ourselves understood as desiring to combine utility with commendable ornament in all that pertains to them. The object has been, thus far, to give hints, rather than models, in description. But as the point to which we have endeavored to arrive will be but imperfectly understood without illustration, we shall submit a few plans of houses and outbuildings, as carrying out more fully our ideas. We are quite aware that different forms or fashions of detail and finish, to both outside and inside work, prevail among builders in different sections of the United States. Some of these fashions are the result of climate, some of conventional taste, and some of education. With them we are not disposed to quarrel. In many cases they are immaterial to the main objects of the work, and so long as they please the taste or partialities of those adopting them, are of little consequence. There are, however, certain matters of _principle_, both in general construction and in the detail of finish, which should not be disregarded; and these, in the designs submitted, and in the explanations which follow, will be fully discussed, each in its place. The particular form or style of work we have not directed, because, as before remarked, we are no professional builder, and of course free from the dogmas which are too apt to be inculcated in the professional schools and workshops. We give a wide berth, and a free toleration in all such matters, and are not disposed to raise a hornet's nest about our ears by interfering in matters where every tyro of the drafting board and work-bench assumes to be, and probably may be, our superior. All minor subjects we are free to leave to the skill and ingenuity of the builder--who, fortunately for the country, is found in almost every village and hamlet of the land.