The gentleman who commissioned this bookmark wanted to express the eternal love he shares with his beloved through the image of two trees wound together and forever inextricable.
So he evoked the legend of Baucis and Philemon. The story goes that Zeus and Hermes
wandered from place to place until they found a couple who would take them in. When Zeus recompensed the couple by fulfilling a wish, they had but one desire: to live and die together. So when they were at the end of their days, Zeus transformed them into trees—an oak and a linden — joined at the base of their trunks.
The love-smitten man believed there was no better anniversary gift for his life-companion. A bookmark. No prize, no “recompense,” just one desire: to be together forever.