Daniel 7:19
'Then I wished for certainty concerning the fourth beast, that was diverse from them all, fearful exceedingly; its teeth of iron, and its nails of brass, it hath devoured, it doth break small, and the remnant with its feet it hath trampled;
Daniel 7:7
After this I was seeing in the visions of the night, and lo, a fourth beast, terrible and fearful, and exceedingly strong; and it hath iron teeth very great, it hath consumed, yea, it doth break small, and the remnant with its feet it hath trampled; and it is diverse from all the beasts that are before it; and it hath ten horns.
Daniel 2:40-43
And the fourth kingdom is strong as iron, because that iron is breaking small, and making feeble, all things, even as iron that is breaking all these, it beateth small and breaketh.