For some reason, I find this really beautiful. This postcard probably dates from between the wars — easily 1920 if not earlier.
The joy of it is that "grannie", whoever she was, has written in phonetic English. To me, it sounds like she's an East Ender (Cockney, as we used to say), based on her spelling of "am". It reads:
Dear ArthaJust a lineto wish youmennie happieburthdays fromGrannie anngrandad xxxxxxI ham sendingyou some stampsto get somthingfor your selfgrannie
It's a wonderful piece of history from a woman who will be long gone. The card was clearly put in the envelope with the stamps. They can't have amounted to much, as any sum over a shilling or so would've been better sent as a postal order. I'd assume she put 10d or so of stamps in the envelope — 90p in today's money and an awful lot for a couple who probably only had the 7s 6d a week (??8) Lloyd George pension to live on.
To a generous and loving Grannie: I salute you from 90 years into the future.