What is said of the fourth kingdom?

Answer

"And the fourth kingdom shall be strong as iron: forasmuch as iron breaks in pieces and subdues all things:
and as iron that breaks all these, shall it break in pieces and bruise." Verse 40.

In what way is this comparison further explained?
What other experience is associated with conversion?
What basis for reconciliation was made by Christ's death?
To whom did Christ become the author of salvation?
How did He encourage His disciples to look for the fulfilment of prophecy?
What, through the prophet Isaiah, does the Lord call the Sabbath?
When were the sun and moon darkened?

Questions & Answers are from the book Bible Readings for the Home Circle