Use "keep dark" em uma frase

1. So, says I, s'pose somebody has hogged that bag on the sly?—now how do I know whether to write to Mary Jane or not? S'pose she dug him up and didn't find nothing, what would she think of me? Blame it, I says, I might get hunted up and jailed; I'd better lay low and keep dark, and not write at all; the thing's awful mixed now; trying to better it, I've worsened it a hundred times, and I wish to goodness I'd just let it alone, dad fetch the whole business!

2. You know something about that Spaniard that you want to keep dark