Glorious's lone .50-calibre machine gun

Why did HMS Glorious carry only one .50-calibre machine gun, and where was it fitted?

It appears to have been an acquired one-off, probably on a bridge wing, although the exact location is uncertain.

HMS Glorious carried a single .50-calibre machine gun because the ship had acquired one rather than as part of a larger installation. The likely position was one of the bridge wings, although the location is recalled from memory and remains uncertain. This accounts for the unusual weapon while keeping its placement appropriately tentative.