For siege works against bold and venturesome men should be constructed on one plan, on another against cautious men, and on still another against the… - Vitruvius

At Halicarnassus, the house of that most potent king Mausolus, though decorated throughout with Proconnesian marble, has walls built of brick which are to this day of extraordinary strength, and are covered with stucco so highly polished that they seem to be as glistening as glass. That king did not use brick from poverty; for he was choke-full of revenues, being ruler of all Caria.

Bricks will be most serviceable if made two years before using; for they cannot dry thoroughly in less time. When fresh undried bricks are used in a wall, the stucco covering stiffens and hardens into a permanent mass, but the bricks settle and... the motion caused by their shrinking prevents them from adhering to it, and they are separated from their union with it. ...at Utica in constructing walls they use brick only if it is dry and made five years previously, and approved as such by the authority of a magistrate.

Dimension stone, flint, rubble, burnt or unburnt brick,—use them as you find them. For it is not every neighborhood or particular locality that can have a wall built of burnt brick like that at Babylon, where there was plenty of asphalt to take the place of lime and sand, and yet possibly each may be provided with materials of equal usefulness so that out of them a faultless wall may be built to last forever.