[JANSENISM]. The Constitutions of the Port Royal Monastery of the Blessed Sacrament. Sacrement. Mons : Gaspard Migeot, 1665. - In-12, brown calf, spine ornamented, spotted edges (period binding). Sought-after edition. It was printed in Amsterdam by Daniel Elzevier on behalf of the bookseller Gaspard Migeot. It is composed of several parts: the Constitutions, written by Mother Agnès Arnauld, the "Notice to the Mistress of Novices", "The Manner of Giving the Novice Habit in the Monastery of Port Royal", "Thoughts on the Ceremony of Dress", "The Manner of Receiving Daughters for Profession in the Monastery", "Thoughts on the Ceremony of Profession", "The Spirit of the Monastery of Port Royal", and the "Regulations for Children". This last part was written by Euphémie Pascal, the sister of Blaise Pascal. A good copy in contemporary binding, complete with the errata leaf at the end. Cracking at the hinge of the second plate, missing headpieces, corners dulled. Title formerly cut at the head to remove a manuscript bookplate.