Lightbulb Vaporizer Help

I've been told by many that while making a homemade vaporizer I need to make two holes in the bottle cap part, then stick tubes in those two holes. My question is how come there has to be two tubes if I'm just using one? What do I use the other one for. I'm sure the anwser to this is very obvious, but I'm feeling a bit on the retarded side today.

 

two holes, the tube goes in one, when you suck air is pulled in by the other

 

It allows the pressure to equalize by letting fresh air come in to replace what u sucked out. Otherwise you wouldn't be able to suck anything I think.

 

You don't need two tubes, but you do need two holes. Then you put your tube or straw through one of them and that should work. I did this and it worked. I did however find the vapors to be very hot and very dry, it hurt my throat a lot. Can this be dealt with, or is it just a necessary byproduct of vaporizing?

 

you can let the vapors cool a bit before you inhale them, silly people. Or you can rig it to some sort of like tube through water or ice...like a vaporbong or something