Subject: Is it possible for a glass to appear to break on its own.

We own a public house. It is known to be haunted but i would like to try and 
find a more scientific explaination to this. We use a glass washer to clean 
all the glasses in the pub. When they come out of the machine they are very 
hot and are then placed back on the shelf in the correct place with the 
others. It has been known for glasses then to just compleatly smash into small 
bits, could this be because of some sort of 'pressure' due to heat? Sometimes 
the glasses smash in your hands. BUT the most weirdest thing which we cant 
seem to explain is sometimes, compleatly random glasses will smash into bits, 
ones that havent been touched and are not even hot. Any answer would be great, 
i hope you can understand how i mean. Please please give me some sort of reply 
if you can. Cheers.

Re: Is it possible for a glass to appear to break on its own.