Not saying bongs don't work. But as a value conscious weed consumer they are a waste.

Of course there are benefits too such as having the smoke cooled down but if you are trying to get the most mileage out of your grass the bong is not the way to do it.

NORML smoking device study

"Disappointingly, waterpipes performed uniformly worse than the unfiltered joint. The least bad waterpipe, the bong, produced 30% more tar per cannabinoids than the unfiltered joint. Ironically, the pipe with the electric mixer scored by far the worst of any device. This suggests that water filtration is actually counterproductive, apparently because water tends to absorb THC more readily than other, noxious tars."

Wiki: http://en.wikipedia.org/wiki/Bong

"However, a 2000 NORML-MAPS cannabis study found that "water pipes filter out more psychoactive THC than they do other tars, thereby requiring users to smoke more to reach their desired effect".
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