Definition of "hang it"

"Hang it, you might say I only took her on out of kindness - poor woman having to put up with a beetling bughound like Peabody. But it's taught me a lesson; no more kindness to married women."

1938, Norman Lindsay, Age of Consent, 1st Australian edition, Sydney, N.S.W.: Ure Smith, published 1962, page 82