Some of the most important surviving works of Old English literature are Beowulf, an epic poem; the Anglo-Saxon Chronicle, a record of early English history; the Franks Casket, an inscribed early whalebone artefact; and Cædmon's Hymn, a Christian religious poem. There are also a number of extant prose works, such as sermons and saints' lives, biblical translations, and translated Latin works of the early Church Fathers, legal documents, such as laws and wills, and practical works on grammar, medicine, and geography. Still, poetry is considered the heart of Old English literature. Nearly all Anglo-Saxon authors are anonymous, with a few exceptions, such as Bede and Cædmon. Cædmon, the earliest English poet we know by name, served as a lay brother in the monastery at Whitby.