YouTube link
... if you fill it with glycerine and submerge it in glycerine, because glass and glycerine have similar refractive indices.
Nothing very special here, but the effect should be good enough to impress small children in your family.
Found at
Reddit.
See http://en.wikipedia.org/wiki/Glycerine about poisonings in 2007 from glycerine contaminated with diethylene glycol.
But yeah, glycerine in and of itself is not poisonous, and is used as a sweetener.
Dude could have learned how to spell tabasco.