be down in the mouth

Don’t let us be down in the mouth till we’re sure there is a danger.

But a man, when he undertakes to advise another, should not be down in the mouth himself.

"Why, yes," says he, and now it was his turn to be down in the mouth.

Why, there's nothing to be down in the mouth about, Mater.

I don't see that there's much to be down in the mouth about.'