The hidden line can be marked typographically (bold, italics, small caps) for those who want to show the fault line clearly as in my poem below, or left entirely concealed.
The reveal of the fault line at the end, like the haiku that ends a haibun, invites the reader to reconsider the formerly stable ground they were standing on from a new perspective.
To construct one: Begin with the line you want to hide---or don’t, and let the two intertwined pieces develop simultaneously! Either way, you’ll build the poem outward from it, choosing words whose edges, pressed together, yield the words of your hidden text in sequence. The poem must stand on its own — the fault line should be barely visible until the reader falls into it.
I'm posting the original fault line, called "Elves Chasm, Grand Canyon," and then another that I wrote, much shorter.
Show me another gray day
and I’ll surrender, start scanning the
cold, wet landscape for a way out.
I’ll climb a bridge and stand, swaying,
trying to judge how many feet I’d fall, if I’d
hit hard enough. Who can take any more
of this gnawing, windy winter?
How can we stand
any more winter?



