Ok navigator. first, if the thermometer was chambered off, the special liquid insidethat makes the balls tell the temperature would not be a problem. 2nd on models ive seen personally the balls are small and it is probably possible to make them smaller... 3rd a two foot bong is rather large...im positive a chamber about a foot long that was sealed and had a tube down the middle of the thermometer would make a nice bong...it wouldn't have to be large at all....or extremely large in this case
you could make it like those liquid filled cups that you put in the freezer so the liquid will freeze. but indead of water it would be the same as a Galileo thermomete.r