it seems the water cools the smoke, which cause the nasties to cool and join causing them to be heavier than air. by let the smoke swirl in the bong these heavy particles gather to the inner surfaces of the bong. some thc is lost i'm sure. that why scraping get you high. but i feel the benefits out weigh the costs.

this is my opinion, that's all. not to be confused with any factual information.

__________________
i'm the guy i've always wanted to be