1:600 scale Hermes, showing basic armament and bridge arrangements, and the seaplane crane built into the island. The elevator was built into the overhang aft. She proved to be rather small, and as such never worked as a fleet carrier to any great extent © Andrew Arthur

The Argus concept was obviously considered sound, for early in 1918, before her completion, the keel was laid down for HMS Hermes. Although she was designed as a carrier from the start, it was obviously not with the benefit of operational experience. Lacking a precedent, her designers made her too small.
With then of World War I construction slowed, the ship being launched in 1919 but not commissioned for another 5 years. As a result she entered service after the much larger but converted Eagle.
With a small aircraft complement, negligible protection and anti-aircraft armament, and low high-speed endurance, Hermes was unsuitable for operations in European waters (except for a short period in 1940 after the loss of both Courageous and Glorious), and she was consequently employed in trade protection in the South Atlantic and Indian Oceans until March 1942.
Her only fleet operation was on 8 July 1940, when her Swordfish aircraft attacked the Vichy French battleship Richelieu at Dakar and scored one torpedo hit.
She was the first purpose built aircraft carrier in the world an there were rather serious stability problems caused by the large starboard island, with fuel having to be carefully distributed to balance the ship.