What is "gladstone bag"

A Gladstone bag is a small portmanteau suitcase built over a rigid frame which could separate into two equal sections. Unlike a suitcase, a Gladstone bag is "deeper in proportion to its length." They are typically made of stiff leather and often belted with lanyards. The bags are named after William Ewart Gladstone (1809–1898), the four-time Prime Minister of the United Kingdom.