The letter on the open page of the book is written to Monsieur.
A book is open to an illustration with the phrase Lettre sur les decouvertes.
A book opened to the page that reads Lettre Sur Les Decouvertes De Herculanum.
A book is open to a section labeled Lettre.
An old looking book is open to a page that says Lettre with an illustration of people in togas grabbing a sphere.