Dr. Egon Spengler: There's something very important I forgot to tell you.
Dr. Peter Venkman: What?
Dr. Egon Spengler: Don't cross the streams.
Dr. Peter Venkman: Why?
Dr. Egon Spengler: It would be bad.
Dr. Peter Venkman: I'm fuzzy on the whole good/bad thing. What do you mean,
"bad"?
Dr. Egon Spengler: Try to imagine all life as you know it stopping
instantaneously and every molecule in your body exploding at the speed of
light.
Dr Ray Stantz: Total protonic reversal.
Dr. Peter Venkman: Right. That's bad. Okay. All right. Important safety tip.
Thanks, Egon.

Tomorrow is a test with a beam in one direction ?

When will two beams be tested in opposite direction ?

Bye,
Skybuck.