h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

And why do they hurt so much when you get the sniffles?

Don't know what they're all about but right now mine are bunged up tighter than the M25 in rush hour and it's annoying.

Mine hurts at the back of my eye when my hay fever is bad. The first time I felt it I thought I had ruptured something in my eye.

I think their main purpose is to make your skull with brain light enough so your neck can actually support its weight. They also apparently help to humidify and condition the air we breathe (mucus removes many particulates) to avoid cold, dry air going straight into the lungs. Or so I've been led to believe...

Yours,
Jake

They seem to be incredibly pressure sensitive. Could they be innate altimeters/depth meters or something?

Well any change in ambient pressure is going to affect an airspace. It's good that the airspaces in our heads aren't enclosed so we can equalise the pressure (other wise it would be crushed or explode depending if the pressure outside increased or decreased).
Here endeth the basic physics lesson

Not exactly. Your eardrums have to be maintained at equal pressure on both sides, otherwise, they rupture. That pressure is equalized through the eustachian tube, which connects to the inner ear. That tube begins at the mouth, right where the jawbones come together, and passes through the sinuses to the inner ear.

So, since the sinuses are part of your pressure regulation system, they are naturally pressure sensitive.

Some research has revealed that the sinuses clean the air of bacteria with pulscating scillia and that the way to relieve the pain of blocked sinuses is to snort salt water (at isotonic solution) in and out 15-18 times a second. Sounds nasty but it's got to be worth a go....

Blimey!
That's a pretty fast snorting rate!

I guess you meant minutes not seconds.

Either way it was fairly disgusting but it did seem to work

This looks like the ideal thread in which to mention that over-zealously attempting to hold back a jet of projectile vomit may lead to one's sinus cavities filling with recycled breakfast .

Quite possibly the only thread in which that comment will ever fit comfortably...if at all.

I think the purpose of sinuses is to increase the resonance of the voice so that it is louder and will carry further. There is no doubt that your voice is much quieter when you have blocked sinuses. I think this feature could enable primitive humans to shout at long distance through the jungles where they evolved.

Snorting salt water in and out? I can manage the concept of snorting it out (although I think that would hurt!) but wouldn't you drown by snorting it in?

x x Fenny

Not at all.
Get one heaped tablespoon full of salt,
Fill a sink with water and stir the salt in.
Then immerse nose in water and snort in and out - any overflow will schloop down the back of your throat. No danger.

Well, isn´t your throat only attached to your air tube and not your food tube? i don´t know the proper names, sorry. Personally I´d rather have a cold than snort salt water.

I'd rather have flu than snort salt water.

Yeah but salt water doesn´t work on the flu. But it is supposed to work against a cold.

I wasn't really concerned about whether it works. I'm quite happy to accept that it does. I have to say that the cure sounds worse than the disease. I was just thinking of all the things that I'd rather do than snort salt water in and out of my nose, and it was quite a long list. Although projectile vomiting isn't on it.