Daniel 7:17 "These great beasts, which are four, are four kings, which shall arise out of the earth."
Daniel 7:7 "After this I saw in the night visions, and behold a fourth beast, dreadful and terrible, and strong exceedingly; and it had great iron teeth: it devoured and brake in pieces, and stamped the residue with the feet of it: and it was diverse from all the beasts that were before it; and it had ten horns."
Like Daniel 2 the fourth kingdom is again shown with iron representing the iron monarchy of Rome.
Daniel 7:19 "Then I would know the truth of the fourth beast, which was diverse from all the others, exceeding dreadful, whose teeth were of iron, and his nails of brass; which devoured, brake in pieces, and stamped the residue with his feet;"
Daniel 7:23 "Thus he said, The fourth beast shall be the fourth kingdom upon earth, which shall be diverse from all kingdoms, and shall devour the whole earth, and shall tread it down, and break it in pieces."
1843 Chart (By Charles Fitch and Apollos Hale)
1850 Chart (By Otis Nichols)