the answer is simple
Glass bowl u are lucky ........do not poke it around where u smoke the glass is getting weak there from getting de tempered from all the use
1 pint of ISO 91% or better
2 some big grain sea salt
3 some table salt
4 a plastic bag (double zip lock) quart size unless u have a big bowl then a gallon and doulbe the iso
u add half the pint to the bag add tablespoon of sea salt add teaspoon of table salt ......put your bowl in and seal
now shake it for a bit let it sit 2 mins shake it again sit for 5 mins and look at it u will see it breaking up and cleaning out .......keep doing this if u feel the iso can not hold more u add more and keep going untill clean
now take the bowl out of the bag when clean and use remaining iso to dip the bowl in to remove the residue and then run cold water over it to remove any salt or iso left ........set out let dry u have clean bowl
clean as u can take it on the air plane ......the cop sees it u say a tobacco pipe and u are free to go with it ,,,,,,clean