In setting out the walls of a city the choice of a healthy situation is of the first importance: it should be on high ground, neither subject to fogs nor rains; its aspects should be neither violently hot nor intensely cold, but temperate in both respects.

There will be natural propriety in using an eastern light for bedrooms and libraries, a western light in winter for baths and winter apartments, and a northern light for picture galleries and other places in which a steady light is needed; for that quarter of the sky grows neither light nor dark with the course of the sun, but remains steady and unshifting all day long.

Economy denotes the the proper management of materials and of site, as well as a thrifty balancing of cost and common sense in the construction of works. ...the architect does not demand things which cannot be found or made ready without great expense. For example: it is not everywhere that there is plenty of pitsand, rubble, fir, clear fir, and marble... Where there is no pitsand, we must use the kinds washed up by rivers or by the sea... and other problems we must solve in similar ways.

Now architecture consists of order, which in Greek is called taxis ... Order is the balanced adjustment of the details of the work separately, and, as to the whole, the arrangement of the proportion with a view to a symmetrical result.

Some springs are acid, as at Lyncestus and in Italy in the Velian country, at Teano in Campania, and in many other places. These when used in drinks have the power of breaking up stones in the bladder, which form in the human body.

There are also kinds of water that cause death, as they run through harmful juices in the soil and become poisonous.

A harmonious design requires that nothing be added or taken away.