How to build a spaceship out of tissue and toilet paper. Earlier we were researching how to build a submarine out if tissue and toilet papers. I can jokingly prove to you that you could build a submarine out of toilet and tissue paper: shove enough in your toilet and flush it -- it clogs and backs up,! Come back in a few days, if you shoved enough in it's still backed up. See? You could use tissue and toilet paper to make a waterproof submarine!
Long ago we've repeatedly made spaceships out of tissue paper, twigs, cornflakes, etc. Does the same proof work? Well, pump all the water and air out of your sewage pipes, in your imagination. If you shoved enough tissue and toilet paper into your clogged toilet, is it still clogged? Depends on your imagination. But it was just a joke proof anyway :)
