Monitoring car values since 1933, it reflects how cars have become increasingly affordable – the £145 list price for a Ford 10 De Luxe (including £5 for an optional sliding roof) was the equivalent of almost two years' salary.
As well as publishing the first Guide to Used Vehicle Values, he had an innovative and enquiring mind and made a number of inventions including the portable hydraulic jack, the electric switch-off kettle, the self-filling fountain pen and the through-the-propeller machine gun firing mechanism.
The founder of Glass's Guide also manufactured cars under the Firefly marque for a short period of time in Croydon.
Glass's other innovations included the first motor auction and the first uniformed attendants at petrol filling stations.
The company expanded into commercial vehicle, motorcycle and caravan values in the 1950s and 1960s, and today it provides electronic and online formats.