What is a bed stacked on a frame directly above another bed called?

A BBC review said that as Bert in "Mary Poppins", which actor spoke a form of Cockney "unknown within 5,000 miles of Bo… Singer Mr. Charles shared his first name with which word for a narrow beam of light? Which large Alaskan island is famous for its giant brown bears? Which Beatles song from the "White Album" includes the line "singing in the dead of night"? The famous Cambrian fossil bed discovered in 1909 near Mount Burgess in British Columbia is made of which rock? What kind of bed has a tall post at each of its corners? In 1947 a Bedouin shepherd found the first of which priceless ancient manuscripts? Which word can describe what a bee does, a con man's elaborate scam and the feeling of a sharp blow?