What do the above have in common?
Well, believe or not they’re different sizes of paper in the English Imperial system. An emperor is the largest size - 72 × 48 (all measurements in inches), an antiquarian is 53 × 31, and an elephant is 28 × 23. There are also double elephants (40 × 27) and grand eagles (42 × 28 ¾), while the smallest size of writing paper is the pott (15 × 12 ½). A bit more interesting than A4, A3, etc!
Quantities of paper also have special terms to describe them:
quire = 24 sheets of paper
ream = 480 or 516 sheets of paper, or 20 quires
bundle = 2 reams
bale = 5 bundles
Quire comes from the Latin quaternī, set of four, four each, via the Vulgar Latin quaternus, the Old French quaer and the Middle English quayer.
Ream comes from the Arabic rizma, bundle, via Old Spanish resma, Old French reime, and Middle English reme.
Sources: The Free Dictionary and Paper measures