1. AFTER settling the positions of the rooms with regard to the quarters of the sky, we must next consider the principles on which should be constructed those apartments in private houses which are meant for the householders themselves, and those which are to be shared in common with outsiders. The private rooms are those into which nobody has the right to enter without an invitation, such as bedrooms, dining rooms, bathrooms, and all others used for the like purposes. The common are those which any of the people have a perfect right to enter, even without an invitation:
2. Those who do business in country produce must have stalls and shops in their entrance courts, with crypts, granaries, storerooms, and so forth in their houses, constructed more for the purpose of keeping the produce in good condition than for ornamental beauty. For capitalists and farmers of the revenue, somewhat comfortable and showy apartments must be constructed, secure against robbery; for advocates and public speakers, handsomer and more roomy, to accommodate meetings; for men of rank who, from holding offices and magistracies, have social obligations to their fellow-citizens, lofty entrance courts in regal style, and most spacious atriums and peristyles, with plantations and walks of some extent in them, appropriate to their dignity. They need also libraries, picture galleries, and basilicas, finished in a style similar to that of great public buildings, since public councils as well as private law suits and hearings before arbitrators are very often held in the houses of such men.
3. If, therefore, houses are planned on these principles to suit different classes of persons, as prescribed in my first book, under the subject of Propriety, there will be no room for criticism; for they will be arranged with convenience and perfection to suit every purpose. The rules on these points will hold not only for houses in town, but also for those in the country, except that in town atriums are usually next to the front door, while in country seats peristyles come first, and then atriums surrounded by paved colonnades opening upon palaestrae and walks. I have now set forth the rules for houses in town so far as I could describe them in a summary way. Next I shall state how farmhouses may be arranged with a view to convenience in use, and shall give the rules for their construction.