First English translation of Spanish Franciscan St. Peter of Alcantara's treatise on mental prayer, accompanied by a life of the saint by the translator and English Franciscan Giles Willoughby. Beatified in 1622, Peter was a friend and spiritual director of Teresa of Avila, and the book translated here was much loved by Teresa, St. Francis de Sales, and Luis of Granada. I could not find any information about the translator aside from what he reveals in the book. Our copy has a distinguished provenance, having been given by the English Oratorian Thomas G. Law to the Duchess of Norfolk in 1864. The book is of great rarity - no copies have come up for auction in over forty years. 8vo (14.5 x 9cm), engraved title-page, printed title-page, [lxviii], 176pp., [iv]. Lacking leaves B4-5 from the 'Life'. Numerous devices in text. Ownership inscriptions to front endpaper, translator's name lightly written on title-page, a few instances of spotting in the text. Bound in 18th (?) century calf with rubbing to spine, small chips at spine ends.