This is CBS Eye on the World with John Batchelor.

Here's John Bachelor.

Continuing with the author and producer, Stephen Moss, his new book is Ten Birds

That Changed the World.

And now we turn to a raven.

I have never seen a raven. I have crows in my life and I respect them. A raven is much bigger. Also, same cleverness, same

intelligence and the legends. Stephen, a very good evening to you to continue with the raven.

You've seen the raven in the Tower of London.

I want to start there because that's part of my association. The Tower of London, it's impossible to avoid it if you read English and American history.

The raven is a very large bird, and I take it, it has something of the aura of mythology around him.

You've met a raven, and he makes a strange sound.

So please explain how big and what the sound is and what you thought when you met a raven.

Ravens are like a crow on steroids. I mean, they're considerably bigger.

They're about the same size as a hawk, a buzzard, you know, red-tailed hawk, that sort of size.

You know, they're a big bird, and they have this very loud, deep call, so they sort of go,

grr, it's where they get their name, actually, It's an onomatopoeic name.

It's from an old Norse word grafen.

And I've met the ravens at the Tower of London.

I've been up close and personal with them with the raven master,

who's a wonderful man there, Chris Scaife, who looks after the ravens.

And they have this extraordinary mythology to them. And that mythology

goes back to early civilizations, the earliest civilisations in North America, in Scandinavia,

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