Iron-hearted

I´ron-heart`ed


a.1.Hard-hearted; unfeeling; cruel; as, an iron-hearted master.
References in classic literature ?
And yet, in every war, their region was infested with iron-hearted soldiers, both French and English, who fought one another for the privilege of ill-treating these poor, harmless Acadians.
"Grandfather," cried Laurence, with emotion trembling in his voice, "did iron-hearted War itself ever do so hard and cruel a thing as this before?"
I have been traversing this iron-hearted town all night.'
The iron-hearted Puritan, the relentless persecutor, the grasping and strong-willed man was dead!
Thou art too gentle and sweet a child for such an iron-hearted father as King Minos.
The man then said: "I must do good, you see, for I was once as iron-hearted as you!" And he vanished, along with the sack.
Ever since Mercury's first and only inspection at close range, by Mariner 10 in the mid-1970s, scientists have wondered how this iron-hearted planet managed to form 4 1/2 billion years ago.