It has been based on the straight line and the right angle.

These, indeed, are the marks which sunder even the simplest civilization from barbarism.

The savage, inconsistent in his moral life, is equally inconsistent, equally unable to 'keep straight', in his house-building and his road-making.

Compare, for example, a British and a Roman road.
The Roman road ran proverbially direct; even its few curves were not seldom formed by straight lines joined together.

The British road was quite different.