What is the tone of this passage?

The infant, during the latter portion of her ordeal, pierced the air with its wailings and screams; she strove to hush it mechanically, but seemed scarcely to sympathize with its trouble. With the same hard demeanor, she was led back to prison, and vanished from public gaze within its iron-clamped portal. It was whispered, by those who peered after her, that the scarlet letter threw a lurid gleam along the dark passage-way of the interior.