Why do things look darker when whet?

Why do many things look darker whent hey are wet? Some good examples that I can think of are any kind of cloth or fabric, carpet, concrete, and wood.

Here’s why.

Correct me if I`m wrong, but I believe QED is the one in the wet shirt.

“It’s always darkest just before the piano falls on you.” --Oliver Faltz

“It has to get worse before it gets worse.” --despair.com

Although the answer supplied above is acceptable, there’s nothing like a Cecil answer to “whet” your appetite for knowledge.