ok..ive gone thru this many times..
recently i dropped my sherlock bubbler and had a very clean break on the neck of it..
here is what u need. Go to any hardware store and buy EPOXY GEL. It is a lil thicker and doesnt run. Next, mix the 2 parts like the pkg says and put the glue n the parts of the glass that the smoke wont be touching, so try to get it towards the outside edge. You can always rub off the excess when u push the peices together. Then it hardens in about 10 min or so, and it should work perfectly. My bubbler hits perfectly, no glue is gonna get in the smoke, and you could never tell it was broken unless it is closely examined. Good luck, and some people jus dont understand the love one can have for a good peice of glass