Smoke is a heated mixture of gasses, vapors and solids. The vapor is almost virtually all water vapor. The rest of it, at least in the case of ANSI issue marijuana circa 1975*, is as follows:
Gas Phase: carbon dioxide, carbon monoxide, acetaldehyde, HCN, acetone, ammonia, toluene, acetonitrile, isoprene, benzene, dimethylnitrosamine, and methylethylnitrosamine
Particulates: tetrahydrocannabinol, cannabidiol, phenol, o-cresol, m-p-cresol, 2,4 and 2,5-dimethylphenol, 1-methylnapthalene, 2-methylnapthalene, napthalene, benzoanthracene, benzopyrene
Out of this miasma, what you want is the tetrahydrocannabinol, the long and pedantic name for the infamous THC of legend. The rest of it is crap (with the possible exception of the cannabidiol, which is a close, but less active relative of THC). Now, when you pass all this stuff through some water, you lose some of the water soluble constituents. Luckily, neither THC or any of its active relatives are water soluble. A bunch of the other stuff, however, is, and passing the lot through some water reduces the presence of those constituents in the smoke. This is a good thing as many of the water soluble constituents are carcinogenic and or toxic. Note that the lower the concentration of the constituents in the water, the better this works - so put new water in your bong once in a while.
Now, as previously mentioned, THC isn't water soluble, and that's why you use water in a bong. THC is somewhat soluble in alcohol, so using alcohol in a bong will somewhat reduce the amount of THC that makes it to you. THC, BTW, is quite fat soluble, and so using any kind of oil in your bong, aside from being gross and messy, will drastically reduce the THC in the smoke that reaches you (bound again, by the same equilibrium based constraints on functional effect).
But wait, what about the cooling effect? Ice bongs work better, right? Well, ice water in a bong cools the smoke down and leads to a denser filling of the post-water chamber (so you get more smoke), but I'd bet - and I'll note that I'm just guessing here - that this cooler temperature probably reduces the effectivness of the filtration because of the general decrease in solubility at colder temperatures.
Ok. The socket is where you put your mix (tobacco and your crumbled solid) and the second hole acts as an air-hole. When you have filled the socket with your mix, you light the mix and suck through the bottle top while holding your finger over the air-hole.
To clear the bottle, either suck all the smoke out or take your finger off the air-hole and blow the smoke out.
So there you have it, a simple bong.
Just choose the one You like and click on the image to see the datails.
Height: 38 cm / 15 in
Comments: In my opinion it's an amazing bong for the price! It can be a little tricky to assemble and there are no instructions. You want to put the rubber pieces in both holes then slowly slide the stem through the bottom rubber piece. Once assembled it smokes great. It has a nice sized chamber for the price. I think it's possible to put too much water in the bong and it can be hard to get continuous suck-age; if you have this happen just poor some of the water out.
Height: 47 cm / 18.5 in
Diameter: 54 mm / 2.1 in
Comments: Overall i was very satisfied with this piece. I was worried I wouldn't get a good color, but I got a red yellow and green one. Its fuckin sick! Jamaican rasta man, hahha. It took a while to get here but was well worth it. you cant get a better bong for this price. Its over a foot high and it hits so smooth. Couldn't ask for anything better right now i just packed it up a couple times and I'm ripped. The bowl doesn't pack too much either, I'm so glad i got this piece. I recommend to all for sure!!!
Height: 29.5 cm / 11.8 in
Diameter: 51 mm / 2 in
Comments: Great bong, but the rushhole needs to be bigger to get a good healthy hit.
It looks juss like 1 on half baked that sir smoke alot uses