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Guess what, Mango?

What's that, Will?

All right, we're going to go way back in history.

You ready?

We're going to the Roman Empire.

I know this is sort of one of your things, so you should get excited about this.

But anyway, the Roman Emperor Vespasian, he actually started construction of the Coliseum

around 70C.

And there's this enormous amphitheater project, and they had to figure out how to pay for it.

And it was paid for in part by taxes, including a tax on urine.

Did you know this?

I had no idea. So you had to pay a tax if you went to the bathroom? Actually, no. Ancient Romans could pee for free, just one of the side

benefits of being an ancient Roman. Totally free. But people collected urine from the public

toilets and actually sold that urine. Now, that's because urea,

one of the most abundant waste products in urine, breaks down into ammonia, which was used for

cleaning. Now, as a result of this, Rome had a bustling urine trade, and Vespasian

censed an opportunity here and decided, you know what, I'm going to tax it. That is both

fascinating and gross. Yeah, you know, you sound like Vespasian son, Titus, who also thought that the urine tax was gross. Isn't that weird? This is not the first time someone's told me. It seemed like Titus. I got that comparison a lot. You, Titus twins, two peas in a pod. Now, in response to this, his dad held up one of the gold coins

that he'd received in payment and asked if it smelled bad. Now, when Titus said, no, Vespasian

...