They used to make swamp coolers that you would put in your car window and it would blow cool air into the car. I always thought those were really cool. Completely unpowered, no electricity. It's such a simple design compared to AC units.

Hah, I had the same reaction to setting up a siphon. That's for when you need to get a liquid up over a hump and down to a lower point.

You draw the liquid into a tube from the source [1] and drag the outlet to a lower point. Then, as if by magic, the higher pool gets sucked through the outlet until it's drained, without any mechanical pump.

https://en.wikipedia.org/wiki/Siphon

[1] you can do it by sucking it in like a straw, but there are less gross ways like using a flexible bottle to provide pumping action

Please describe it

You basically have a fan that sprays a very fine mist. The water evaporates, and in doing so the temperature of the air drops. Note that this only works when humidity is low enough for evaporation to actually happen. If the humidity is too high this doesn't work.

Edit: wiki goes in to way more detail about other methods I was not familiar with: https://en.wikipedia.org/wiki/Evaporative_cooler

I dunno, I think that evaporation happens even if there is a lot of humidity in the air. The fastest (hottest) water molecules are going to escape the liquid water. The wind will carry them away.

I think this phenomenon does not take in account the wind. That actually if you have water to wet yourself and a fan you can cool you down.

Not sure though since I seem to be alone to think so.

You've repeated this take twice, but it is still wrong. Yes, the fastest water molecules on your skin escape. But you also have water from the air also latching onto your skin which you aren't accounting for. You're free to see how well evaporative cooling works when there is a lot of water in the air. You can just take a fan into a bathroom and run the hottest shower possible for a few minutes.

I live in Southwest US where it’s common to use a swamp cooler (aka evaporative cooler) for your house. Instead of the normal refrigerated air unit that sits outside your house, there is basically a box with a big fan that pulls air across a big wooden or synthetic “sponge” and pushes it into your house ducts. A small pump like in a fish tank continuously pulls water across the sponge to keep it wet. You leave a couple windows in your house cracked open to leave an exit as new cold air is pushed in. Has a nice humidifying effect which is good in the desert too!