What is the use of an epergne?

Answer 1

a comb

Answer 2

It is a very decorated piece of silver, typically with stacks or layers of flat, plate like silver pieces, sometimes with slightly curved edges.
Sometimes little baskets hung off the sides.
Yes, flowers could be shown. But more often fruit that was "sugared" was displayed during a meal, and then served for dessert.
You usually find them from the turn of the century, 1900's and into Victorian times.
They are hard to find, quite expensive and you want all the pieces.

Answer 3

it's used as a centerpiece, to hold flowers, or fruit.