Small Girl: "The air seems like it's kind of dirty."
Large Boy: "And it smells like poo."
Bow-tie Boy: "The problem is that London's fog isn't just clean condensed moisture vapor. It's that plus all the pollution from smoke and soot burning off from the coal and oil they used for fuel. Today we call it smog."
Small Girl:" Really? I didn't even know smog existed back then."