The mystery cards have been decrypted, thanks once again to Klaus and his blog readers. But even more interesting is that the two cards I posted were bookends to a longer correspondence. And it opens up a century-old love story between "Arthur and Dolly" thanks to some fascinating historical sleuthing. You can read all about it here, along with the messages on the cards:
https://scienceblogs.de/klausis-kry...ment-1718675