Invisibules

“So, Professor Einstein, will you tell the listeners how you got started in science?”

“Vell, of course at first I vas rather fascinated by the universe, and the vay matter and space and time interacted, and I vas sure there vere some interesting vays in vich it could all be described by some geometrical constructions. But mainly I had seen some scientists playing vith liquid nitrogen, and I vanted to have some fun vith it too.”