The original set up was vacuum not pressure Ian - the only car I know of to use pressure wipers was the VW Beetle whichs used pressure from the spare tyre.
VW screen washer system was pressurised via spare tyre but I don't think wipers ever were. Early vee-dub beetles also had cable brakes too, so at least they got that bit right!
The VW Beetle 'Standard' was made into the mid-'fifties still with cable brakes and a non-synchro 'box.
Stripped of what then passed for luxury in the de Luxe, it was a very pleasant car to drive instead of the PA in the 'sixties, though rare even then in the UK.