Symmetry in a poem?

Lewis Carroll wrote a poem--a square poem. It's only a few lines and it is not remarkable as a poem, except for the way that it reads. It's written symmetrically, so that you can read it from left to right and top to bottom. Now, that is remarkable!

This is not an easy thing to duplicate. I've been working for several days on my own symmetrical poem, as part of my one-poem-a-day challenge. Perhaps you'd like to try to write one too?