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Message-ID: <221412Z30111993@anon.penet.fi>
Newsgroups: alt.drugs
From: an53943@anon.penet.fi (Mary Jane)
Date: Tue, 30 Nov 1993 22:08:58 UTC
Subject: Gravity.Bong.FAQ

Here is an article I hope readers feel is helpful, in response to all
the discussion about gravity bongs, how they work, and how to make them...

********************* BEGIN ARTICLE ********************

THE GRAVITY BONG:

    I am a senior mechanical engineering student.  My specialty is 
design and prototyping.  I have worked for several companies 
learning how to prototype, and this comes in really handy for some 
of my "other" projects.  Here is a pretty simple one...

    I was introduced to the gravity bong by a friend.  He told me 
the full name as described to him was the "Afghanistan Gravity 
Bong".  We were sitting around one night and decided to try one 
out.

    While I could go into detail concerning the mechanics of the 
bong's operation, I don't think that is really necessary.  The 
reason it is called a "gravity bong" and not something else is 
this is what someone called it, that is how they described it to 
their friends, and now it is an accepted term for the following 
setup.  I have observed some people on the net arguing about 
gravity vs. pressure vs. whatever.  If you have comments like this 
as a result of this description, I refer you to: 
alt.engineering.geeks.  The type of argument I have observed would 
have been halted a long time ago by declaring a "TECH TIME OUT !!" 
at our school.  Take a hit man.  I feel better now having said all 
that, so... on with the important stuff...


GRAVITY BONG OPERATION:

STEP 1:
    Place the bottomless bottle into a water source such as a 
bucket of water, sink, bathtub, larger bottle, fishtank (just 
kidding), etc...When the bottle rests on the bottom, the mouth 
piece should be above the water level enough to grip the bottle.  
I'm not sure if warm or cold water is best, or even if it makes 
much difference seeing as the smoke is not bubbled through it.

STEP 2:
    Pack the bowl and place it on the mouth of the bottle.

STEP 3:
    SLOWLY!! draw the bottle out of the water, while lighting the 
bowl.  The herb should really burn and the smoke will look 
intimidating.  Stop when: a)the herb is all ash (preferable), or 
b)when the bottom of the bottle is still an inch or so below the 
water level in the bucket.  Begin preparing yourself for a huge 
hit.

STEP 4:
    CAREFULLY remove the bowl without letting the bottle move 
downward (up a little is o.k., but don't lwt the bottom come out 
of the water), exhale deeply, and place your mouth over the 
opening.  Inhale quickly and completely, allowing your head to 
move downward.  Try not to drink any bong water as this kind of 
sucks! (although its like learning to swim, it's bound to happen a 
little).  

STEP 5:
    Don't cough and hang on tight!



                                                        
                                 PACKED                 
                                 BOWL >> $$             
             I  I                       I\/I            
BOTTLE  >>  /    \         BOTTLE  >>  /    \           
           /      \                   /      \          
    |     /        \     |     |     /        \     |   
    |~~~~|~~~~~~~~~~|~~~~|     |~~~~|~~~~~~~~~~|~~~~|   
    |~~~~|~~~~~~~~~~|~~~~|     |~~~~|~~~~~~~~~~|~~~~|   
    |~~~~|~~WATER~~~|~~~~|     |~~~~|~~WATER~~~|~~~~|   
    |~~~~|~~~~~~~~~~|~~~~|     |~~~~|~~~~~~~~~~|~~~~|   
    |~~~~|~~~~~~~~~~|~~~~|     |~~~~|~~~~~~~~~~|~~~~|   
     \__________________/       \__________________/    
            BUCKET                      BUCKET          
                                                        
            Step 1                      Step 2          
                       \/ = BOWL                        
              %        $$ = HERB                        
 LIGHTER  __  *%       ** = LIGHTER FLAME               
     >>  |__|@**                                        
              $$                        SUCK            
     /\      I\/I               ||                      
     ||     / . .\              ||      I..I            
     ||    /. . . \             ||     /. . \           
     ||   /. . . . \            \/    /. . . \          
         |. . . . . |                /. . . . \         
BOTTLE  >|   SMOKE  |               |. . . . . |        
         | . . . . .|               | . . . . .|        
    |    |~~~~~~~~~~|    |     |    |~~~~~~~~~~|    |   
    |~~~~|~~~~~~~~~~|~~~~|     |~~~~|~~~~~~~~~~|~~~~|   
    |~~~~~~~~~~~~~~~~~~~~|     |~~~~|~~~~~~~~~~|~~~~|   
    |~~~~~~~WATER~~~~~~~~|     |~~~~~~~~BONG~~~~~~~~|   
    |~~~~~~~~~~~~~~~~~~~~|     |~~~~~~~~WATER~~~~~~~|   
    |~~~~~~~~~~~~~~~~~~~~|     |~~~~~~~~~~~~~~~~~~~~|   
     \__________________/       \__________________/    
            BUCKET                      BUCKET          
                                                        
            Step 3                      Step 4          

THE DESIGN:

FIRST TRIAL:
    First, a 2-liter bottle and a suitable bucket were obtained 
from the apartment.  I cut the bottom off the 2-liter bottle and 
set it aside.  I was able to find a couple of screw on caps, one 
of which was of the metal variety.  I cut a rough hole in each, 
and glued them together, with the cup sides facing out.  Into the 
side with the metal cap, a piece of screen was placed and fit real 
nice.  We were forced to build this little thing because we didn't 
have a bowl handy.
    This worked o.k., but quite a bit of air flowed in for the 
quantity of herb which was consumed.  Also, it was a pain to 
unscrew the cap after lifting the bottle.  Overall, we all ended 
up having a great time and the first trial was still a success.  I 
leave this historical description in here because: a)this may be a 
good enough system for you, or b)you are also in a pinch for 
something right away as we were!

SECOND TRIAL:
    Having decided the activity was fun enough to warrant further 
development of the gravity bong, and having access to a machine 
shop, I designed a bowl just for this purpose.  This incorporates 
a nice sized burn chamber (approximately = to 5 bat hits from a 
small bat), a small screen, and an o-ring seal to prevent air from 
passing anything but the burning herb.  It drops out a pretty 
hefty ash after each hit.
    Here is a horizontal sketch of my gravity bowl design:

   FITS            ___                                  
    IN       ____O|   \            _______              
  BOTTLE >> /          \__________/  _____|             
           |                        |+                  
           |-----------------------/ + << SCREEN        
HOLE  >>>> |-----------------------\ +                  
           |            __________  |+____              
            \____      /          \_______|             
      O-RING >> O|___/                BURN              
                                     CHAMBER            

    You could make the dimensions to whatever you think may work 
best.  I put a 1/4 in. hole through the bowl, with a 3/8 dia. burn 
chamber that is .400 in. deep.  It fits nicely inside a 35mm film 
canister for storage and TRANSPORTATION to parties (no plans to 
build more, though several friends have already tried begging!).
    This new bowl works very well and burns quite efficienty, 
filling the bottle with dense smoke.  The only change I have made 
to the apparatus is to offer the option of a milk jug in place of 
the 2-liter bottle, with a plastic adapter atached to the jug 
which makes the mouth the same size as a 2-liter bottle.  
        I built my setup some time ago, but the other day someone on 
the net mentioned using a tuba mouthpiece.  Not a bad idea.  Also, 
people have said they used aluminum foil with holes poked in it.  
The point is to get a lot of burning done without using an overly 
large volume of air.

TRIAL THREE:
    This has not been done yet, but the plan is to design a multi-
user setup using a larger water bottle (like the Poland Springs).

TIPS:

To get really wacked, breath back into the bottle, allowing it to 
rise back up to the beginning of step 4, and inhale again.  Do not 
however, deprive yourself of too much oxygen.  I used this method 
and took a full minute to take the hit, breathing in and out, and 
was immediately wacked, staying that way for several hours from 
one hit!

Have a "Gravity Party" with many friends - lotso fun!

Some people like to push the bottle to the bottom, and then 
inhale.  While this does act to push the smoke into your lungs 
(kind of like breathing in a balloon), I don't really feel it is 
any faster.  If you try this, don't displace so much water that 
the bucket overflows.

If it is your first time trying the system, do some trial runs 
without packing the bowl and lighting it.  This is a must for a 
first time user from the point of view of risk reduction (won't 
chance losing precious smoke).

********************* END ARTICLE ********************
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Bowl Suggestion
by RT
I read the faq on the gravity bong and there was a key element missing.
The key to a good gravity bong is construction of the bowl mechanism. 
Using a standard glass or metal bowl connected to a long tube forces
the smoke to be filtered through the water, like a true bong.  
Like so:


                          \ @@@@@@@ /
                           \ @@@@@ /
     Hole in lid            \ @@@ /
     Duct tape to seal       \   /
  (it melts a little)  _____/|  |\_______     Two liter pop bottle
                       ||    |  |      ||        (not to scale)
                       ||----|  | ---- ||
                       ||    |  |      ||
                       ||----|  | ---- ||
                        |    |  |      |
     ^^^^^^^^^^^^^^^^^^^|^^^^|  |^^^^^^|^^^^^^^^ begining water level
                        /    |  |       \
                      /      |  |         \
                    /        |  |           \
                  /          |  |             \
                /            |  |               \
              /              |  |                 \
              |              |  |                 |
              |              |  |                 |
              |              |  |    monster      |
              |              |  |     rip!        |
              |              |  |                 |     -- lift bottle
              |              |  |                 |
              |              |  |                 |
              |              |  |                 |
              |              |  |                 |
              |              |  |                 |
              |              |  |                 |
              |              |  |                 |
              |              |  |                 |
              |              |  |                 |
              |              |  |                 |
              |              |  |                 |
              |              |  |                 |
              |              |  |                 |
      ^^^^^^^^|^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^|^^^^ end water level
              |                                   |
              |                                   |


    When full unscrew the lid and bowl and enjoy
       the biggest rip of your life!