A modified Dayton-Wright USD-9A became, in 1921, the first aircraft to feature a pressurised cockpit. The aircraft had “..an airtight spherical chamber in place of a cockpit. The chamber had only a control stick and small portholes to view the instruments, which had been located outside..” (via)
The bottom photo is via the SDASM Archives on Flickr. The photos appear to be showing different stages of the aircraft’s development?