cool, similar to how tempered glass works in most car windshields, most small cracks will be closed back up by the surface (in compression) but if a large enough crack forms (someone breaks the glass) it shatters into thousands of pieces.

another video here where we can see the "drop" when it shatters :
http://www.youtube.com/watch?v=Pdy2_vi0FfM

An excellent demonstration of the fluid like properties of glass. I didn't know about this.

I want ultra super slowmotion video of that happening, NOW!

That was actually super intresting.

"Can't be broken" - Them's fighting words.

^ yeah... more like can't be broken when gently tapped on. i don't know about anyone else, but when i use a hammer, i hold the base of the handle and swing it more than 10 degrees.

That was fascinating, I didn't know such things at all.

bison_ravi's link has some slow motion at the end.

Very interesting. Thanks.

>> ^cybrbeast:
I want ultra super slowmotion video of that happening, NOW!

@krumzy - just wanted to mention that most windows in cars do use tempered class although the windshield does not. Windshields use laminated safety glass so that there is no shattering. A windshield is constructed by bonding exterior layers of annealed glass to a middle layer of plastic.

BTW - this is a demonstration that they perform every hour or so at the Corning Museum of Glass... a fascinating place to visit.

I've seen these things hit about as hard as can be managed with a hammer. I'd be quite surprised to see anyone break one without resorting to far more drastic measures.

>> ^E_Nygma:
^ yeah... more like can't be broken when gently tapped on. i don't know about anyone else, but when i use a hammer, i hold the base of the handle and swing it more than 10 degrees.

*engineering

Adding video to channels (Engineering) - requested by oxdottir.