From Wave form to Icicles

I don’t know how it happened…as I was moving my cursor across an Audacity unsaved recording that was playing. Suddenly my wave form image looks like icicles or stalagmites, hanging from top of the track area.

How do I see the regular wave form again?

Put the mouse cursor on the vertical scale* and press the right mouse button (repeatedly).
(* the cursor turns into a little magnifying-glass icon when you do that).
putting cursor on vertical scale activates zooming in on waveform.gif
http://manual.audacityteam.org/man/zooming.html