hey, i never have seen these glasses! they are interesting indeed.
i see two probems tho.
1: dont they need a rubber seal? and if so, how does the rubber seal react to warm naphtha?
2: i do have a good friend who is not much interested in psychonautics, but happens to be a chemist. he warned me expressively that when i mix acids and bases the volume would increase and this would be relay dangerous if i use containers that are screwed tight - especially because the used liquids are all but harmless. now. he said as long as i knew this and i payed attention to release the pressure (as mentioned in the tek anyhow) i would be fine, but this IS a potential source of danger that can be easily avoided with adequate equipment (a glass plug just would pop out of the bottle instead of the bottle blowing up).
sadly most flasks with glass plugs are really expensive, and when just browsing amazon i did not find anything good. however, in the end i did find a shop that had some very nice flasks at a reasonable price, so i ended up buying these:
they are called "wide neck glass reagent bottle with stopper" and most labor suppliers sell them.
i ended up paying 8€ fora 1l flask and 10.5€ for a 2l bottle. i think considering safety and chemical resistance this is money very well spend.
FASCINATING