Glass Experiment

Two days ago I found a glass cider jar in the the trash. Could I turn it into a massive bell jar?
Could I clip the neck off and make it short enough to fit in the kiln? Wherever there is a hard corner on a glass jar, there is a very high chance that the glass will crack in a direction you don't want. But I clipped it none the less!:



Then I cleaned it and put it in the kiln over top of two molds instead of just one. The next morning:

See those hairlines in the glass? Those are cracks. The back was worse. I guess the glass was so thick that it needed extra time to cool down so that different parts of the glass weren't contracting at different speeds. So it was an experiment for the recycling pile. Easy come, easy go. Today I loaded up the kiln with tried and true salsa and jam jars.