Fontaine de la Vérité de l’Amour
The Fountain of the Truth of Love was created by Merlin, and is associated with enchantment and the revelation of hidden truths. It is said that when lovers drink from this fountain, their true feelings are unveiled, allowing them to express their emotions honestly and without artifice.
The novel L’Astrée, is a seventeenth-century novel begun by Honoré d’Urfe (1567-1625) and concluded by his secretary, Baro. It is in the section by Baro that the fountain is mentioned.
Source
L’Astrée | Honoré d’Urfé, 1607-1627