After reading about Jana Dambrogio, the Thomas F. Peterson conservator at M.I.T. Libraries, who is analyzing how letter writers have sealed their letters until they reached the intended recipients, I was reminded of a valentine in the Graphic Arts collection. http://www.nytimes.com/2015/09/18/arts/design/a-trove-of-letterlocking-or-vintage-strategies-to-deter-snoops.html
Dambrogio has a great website for letterlocking, but I was not able to find and solve the secret of our valentine. http://www.janadambrogio.com/timeline
If you have time, please print out this double-sided 18th-century valentine and solve the puzzle. The heart is complete at the beginning and then, each section of the poem should be read in full as you unfold. Please send me your solution. Thank you.