That's the same chalkboard Mega Man used to later explain the "gag reflex".
I was taking a class on ceramics when I made this comic, and while I found this information on glass interesting, I also thought it would make the perfect fodder for an incredibly boring lecture. In case you're wondering, the full text is:
You see, glass really isn't a solid or a liquid. It's classified as an amorpohous solid because it doesn't have a crystlline structure like most solids.
Now, because it doesn't have a crystalline structure, it can actually flow over time, like a liquid. Of course, the amount of time to see an actual flow is so huge that not enough time has passed since the beginning of time, but it does still flow.
Now, when working with glass, there are four important points. While the viscosity is the same at each point, the temperature depends on the type of glass.
At temperatures above the working point, the glass can be blown and molded. At temperatures above the softening point, the glass will deform under its own weight.
At temperatures above the annealing point, stress on the glass can still be relieved by plastic deformation. However, at temperatures below the strain point, stress can't be relieved without fracture.