Our brains don’t work well in hot weather. According to a new study, we’re sharper when it’s cold, possibly because the brain thinks: “Where are my fingers? I must find my fingers.” Plus, the neurons don’t have to fight their way through the torpid humidity.

This are why we is smarter up here in the steppes. And it explains why I did not blow up six teenagers a few days ago.

Let me back up a bit. Long ago I was humiliated by a propane-exchange clerk, and the sting has never faded. I brought in an empty tank to exchange for a new one, and he made a wry expression when he picked it up. “You’ve still got some in there,” he said.

“What are you, the propane whisperer?” I wanted to snap. He probably was right — if you heft the empties a few times a day, you get a feel for which tanks are bone dry and which still have some propane inside. Ever since then, I have tried to develop the knack, making a great show of my know-how: lifting the tank, knocking it on the side with a wrench and saying, “Sssshhhh. I’m listening for the note. If it’s E-flat, I’ve got enough to cook dinner.”

It’s all just a show for onlookers, of course. But I haven’t run out in years, I’m proud to say. There hasn’t been a single cookout where I’ve run out of fuel. I have a secret trick, and it’s —

No, not yet. That comes at the end of the column. You’ll have to wait.

Anyway, the grill instructions always give you a healthy fear of propane. You’re instructed to turn on the gas slooooowly — crank the spigot fast and the gas jams up, or something — and then push the electric starter button. Click! Push it again. Click! And again. Click! And again. Nothing?

Sigh. Turn off the gas, leave the lid open, check into a motel for the night. Return the next day; the gas should have dissipated. Try again, but this time put a match through the emergency ignition hole.

Then, extinguish eyebrows. Draw on new eyebrows with a pencil. Turn on the other burner, which will hiss for a few minutes before a ball of flame arises and people on the other side of town say, “Looks like trouble at the refinery.”

I don’t worry about the tanks exploding, because the idiot-proof valves are designed to keep gas from leaking out. But the other night, Daughter and friends wanted to sit around a fire outside, and because she’s leaving home for another country in two weeks, I’m inclined to honor any request.

“Can you make a fire?”

“Sure. Want a car?”

“Just a fire would be great.”

The fire pit came from some propane-product Chinese factory that burned to the ground years ago — look on Google Earth, you’ll see a crater — and it never has worked very well. It has a gas ring under a heap of lava stones and an electric-spark starter with the potency of a wet firefly, necessitating the use of a match to ignite. In short, it’s junk, and I imagine the big-box store that sold it figured they didn’t have to worry about repeat customers because they’d all be blown to bits soon enough.

I hooked up the tank to the hose and turned on the gas. There was hissing from the outside of the valve. Altogether now, men, what’s your first instinct? Right: Light a match to see if anything catches on fire, because we are daredevils who scoff at danger. We’re also idiots.

Some of you may be rolling your eyes at this point: “Son, this is why God made duck tape.” And then I say, “It’s duct tape, with a T,” and then the guy from the propane exchange pops out of a big tank, laughing, with a duck bill on his face, and I awake from the nightmare. Point is, you ought not use tape in a situation that includes “leaky gas line.”

As for lighting a match, well, I’m not on YouTube this week, screaming and rolling on the grass and shouting, “Hold the camera in a horizontal orientation, you idiot. Also, some water would be great!” That’s because it was a cool night, not a hot one, and, hence, my brain was working better. Ten degrees warmer and I would have said, “There could be a snake trapped in the line that’s makin’ that sound. Prolly be OK.” Then I blow up six kids.

So, yes, the study is correct. But to clarify, it was based on the cognitive abilities of college students who had to answer 12 questions in the morning after sleeping in an un-air-conditioned dorm, which is little like judging the national church attendance rate based on a survey of frat members on a Sunday morning during pledge week.

Oh, my secret trick for never running out of propane on a cookout? Have an extra tank.

Like I said: We’re just smarter up here.