4th proof. Etched with vinegar, hydrogen peroxide, and kosher salt. Not as nontoxic as I originally thought. Combo creates peracetic acid, a weaker version of acetic acid, and over the long haul, in indoor situation, not cool. Might be OK if you did your etching outside, in a wind. Pretty weak vapors. But not good for school situation, which is what I'm researching for. Has to be VERY nontoxic. Until then, drypoint and monotypes for the kids.
Study I've been working on since Monday, 9.16.13. Plan to make a drypoint of the subject, either a Transfiguration or an Ascension.