Do you know where the phrase,"for crying out loud." derived from?

Question

I'm reading a book"Heavens to Betsy" in my office, that have curious sayings in them. I came across "for crying out loud". Here's what it says in short : "An ejaculation,usually indicating complaint or astonishment, (that I get)Many of the users of this expression would be shocked to learn that it is in the category known as a minced oath; that is,a substitute based on,but slightly different from a profanity."
LOL. Who else on this earth knew that!? Gesh. :-)

Answer 1

Meaning

For Christ's sake.

Origin

A minced oath.

Answer 2

I never thought about it that way...that is funny.