Wire framed spectacles had existed since Victorian times but found mainly on older people.
The attitude to spectacles which had produced the monacle and pince nez had vanished.
Rather than wearing glasses on an ad hoc basis, it became socially acceptable to wear them all the time; especially among the younger generation.
Photo: USA Studios London & Provinces
Above photo dated about 1916: Age about 19 years old Estimate: born 1897 ± 5 years