A clever means of categorizing the size of rivers. It does this by looking at joins of tributaries. Each time two tributaries of the same order join together then the river goes up in order. So the start of a stream from a spring is the outermost branch — first order. When two first orders join together, the river is classified as second order and so on.

The largest river by Strahler stream order classification is the Amazon at twelfth order. This means that at least two order 11 rivers had to merge together before the river emptied into the sea.

Strahler stream order: Streams, rivers, the Amazon and how to organise them.

I think it would be interesting if we could see the real shape of your favourite crossing marked on the road. It’d probably help more people cross and traffic get stopped less. And, hopefully, no casualties.

Our senses are built to take in information at human pace

The real shape of a crossing

You could do worse than follow this for most simple branding. Think of a suit where about 60% of the colour you see is the suit, 30% the shirt and 10% accent or highlight with the tie. Classic.

60-30-10 Colour rule