Hollow Tube How-Tos???

[LAJ]

I have some hollow tubes that I received in a trade. I was wondering if anyone can tell me how I'm supposed to work these? They're 104 COE. I had thought that they would be useful in making hollow beads, but can't figure out how for the life of me.

[playswithfire104]

If you make regular beads they will come out with bubbles in them. Pretty cool.

[debkauz]

I have some too but haven't used them yet. Tink uses them a lot, I think. I hear they are very shocky and should be preheated but that's about all I know so far.