Still Waiting

My letters are a heatless flame
Burning with no cause.
A soundless scream,
A wisp of steam,
And yet, you give them pause.
Roll my letters on your tongue;
Never try to swallow.
Hurl them all

From wall to wall.
No echoing will follow.
I've searched them all for substance,
My letters hollow, wordless, weak.
They've no reason to be writ or read.
Yet, we wait for them to speak