There will be no propriety in the spectacle of an elegant interior approached by a low mean entrance. - Vitruvius

In felling a tree we should cut into the trunk of it to the very heart, and then leave it standing so that the sap may drain out drop by drop throughout the whole of it. ...Then and not till then, the tree being drained dry and the sap no longer dripping, let it be felled and it will be in the highest state of usefulness.

Consequently, limestone when taken out of the kiln... though its bulk remains the same as before, it is found to have lost about a third of its weight owing to the boiling out of the water. Therefore, its pores being thus opened and its texture rendered loose, it readily mixes with sand, and hence the two materials cohere as they dry, unite with the rubble, and make a solid structure.

To guard against this, we must proceed as follows. Let down a lighted lamp, and if it keeps burning, a man may make the descent without danger.