Scifi fans know that debate about gun control is besides the point. Guns won't save anyone from rampaging Terminators, aliens, or Jason Voorhees. Liquid nitrogen will. Here's how to make some on a super-low budget, for home protection!

As everyone knows, no home is safe without a security company sticker on the door (to stop regular criminals) and a vat of liquid nitrogen in the hall (to take care of today's alien, robot, supernatural, or genetically engineered supercriminals).


But why pay for pricey liquid nitrogen delivery (or bother the neighbors for a cup of nitrogen when you run short) when you can just make it yourself? Follow these easy steps to making some liquid nitrogen. It is so much easier than just giving up your paranoia.

Now, this is a secret that Big Nitrogen doesn't want you to know: Nitrogen is all around you. Yes, even now! What you're breathing in and out is almost eighty percent nitrogen. You're living off the twenty percent oxygen in air (and probably being slowly killed by the trace amounts of other elements).

Don't you feel silly? Here it was all around you, and you were paying for it. But don't feel bad. Just get started!


The first step in the process is compressing the regular old air you get for free. You'll need to get the pressure up to 3,000 pounds per square inch, so I suggest everyone in your household piling on the inner tube you got for the pool.

For the next step, you will need that perfect metaphor for the Internet: a series of tubes. This particular series of tubes will be a way for the gas to shake of that heat from compression, the way a lunatic shakes off being crazy if you shove them in a straight jacket. Keep it pressurized, keep allowing it to radiate heat. Soon it will become cooler.

Like passengers on an over-crowded bus, a recently-released gas will begin to expand. Unlike the passengers, however, it won't do it via the judicious use of elbows. Gases need energy to expand, and they get energy from their environment. That's why they feel cool. They "suck" the heat out of their surroundings in order to get that energy.


The kids will most likely complain that they're getting cold. Just tell them that if they don't take their turn helping out, they will have to deal with it when Pumpkinhead comes a-knocking.

That will shut them up.

Finally, the gas will get so cold that, even when the pressure is lifted, it won't immediately expand. It will be compressed into liquid form.


The rest is simple; pour it quickly and neatly into your vacuum-insulated thermos. Do try to save up and buy your own. The rented ones are a second-rate and expensive. Et voila!

Next time: How to make sure a vat of boiling iron swallows mechanical pursuers and not your pets. Fences aren't enough!


Via: How to Do Things and Ask the Van.