History of the Dugout

[bgray]

I know this is not specifically an "officiating" topic, but someone may know the answer.

I've looked everywhere for a "definitive" explanation of why the dugout was invented. Obviously, it's called a dugout because the bench area is partially below ground.

But WHY was it originally built that way?

(I've heard two different logical answers, which I'll withhold until some of you have time to respond.)

I'm hoping for a "documented" history as opposed to opinions, but opinions are welcome too. ;-)

Thanks!

- Brent