I found this heart-shaped book of hours on pinterest and was immediately intrigued, so I’ve started researching heart-shaped (or cordiform) manuscripts in general. So far, I’ve found a few, but none are accompanied by an abundance of information. So far, I’ve found four thanks to this post, which has some great photos, too. I particularly enjoyed a Danish book of ballads made in the 1550s and now owned by the Royal Library of Denmark (KB, Thott 1510). The Chansonnier Cordiforme (BnF MS Rothschild, Occ. 2973) was another heart-shaped medieval songbook, this one French from the 1470s. According to Eric Jager in an excerpt from his book The Book of the Heart, cordiform manuscripts were often songbooks containing love songs – for obvious reasons, I think. Jager also points out that the Chansonnier Cordiforme is the only surviving cordiform songbook to be illustrated. The manuscript depicted at the top of the post is a book of hours made in Picardie, France in the 15th century; it is the Bibliotheque Nationale de France’s MS Latin 10536. The image below is a facsimile of the Chansonnier Cordiforme owned by the University of Cincinnati Libraries’ Rare Books Collection.