Daniel 2:40-41

2:40 Then there will be a fourth kingdom, one strong like iron. Just like iron breaks in pieces and shatters everything, and as iron breaks in pieces all of these metals, so it will break in pieces and crush the others. 2:41 In that you were seeing feet and toes partly of wet clay and partly of iron, so this will be a divided kingdom. Some of the strength of iron will be in it, for you saw iron mixed with wet clay.