All these soft kinds [of stone] have the advantage that they can be easily worked as soon as they have been taken from the quarries. Under cover, they play their part well; but in open and exposed situations the frost and rime make them crumble, and they go to pieces. On the seacoast, too, the salt eats away and dissolves them, nor can they stand great heat either.

Next I must tell about the machine of Ctesibius, which raises water to a height.

When the juices of trees have no means of escape, they clot and rot in them, making the trees hollow and good for nothing.

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.

In fact, all kinds of men, and not merely architects, can recognize a good piece of work.

All these soft kinds [of stone] have the advantage that they can be easily worked as soon as they have been taken from the quarries. Under cover, they play their part well; but in open and exposed situations the frost and rime make them crumble, and they go to pieces. On the seacoast, too, the salt eats away and dissolves them, nor can they stand great heat either.

There are also half bricks. As the bricks are always laid so as to break joints, this lends strength and a not unattractive appearance to both sides of such walls.