I'm trying to expand my breadmaking skills from conventional yeasted
breads. I couldn't find a local source of starter so I set up a rye-based
starter, and then fed it with Gold Medal organic unbleached wheat flour
for a couple of days. It started bubbling nicely, and rather than throw
the excess away when I fed it, I made a sponge.

I've been reading Susan Jan Cheney's book Breadtime, and found its chapter
on "natural rise" bread quite interesting. Would this be an example, or
is it sourdough, despite the very short starter development time?

I let the sponge mature overnight, and about an hour ago I mixed in salt,
olive oil, and enough organic unbleached flour to make a sturdy dough. It
seems to be rising nicely, and has a definite sour smell. Of course, the
bread may be a disaster when it bakes-- who knows.

Ray