The signature of Byrhtferth appears on only…

1011 CE

The signature of Byrhtferth appears on only two unpublished works, his Latin and Old English Manual, and Latin Preface.

He had also composed a Latin life of St. Egwin, compiled a chronicle of Northumbrian history in the 990's, had written wrote a Latin life of Oswald of Worcester (the Vita Oswaldi) about the year 1000, and it is suggested that he is responsible for the early sections of the Historia regum, or History of the Kings, attributed to Simeon of Durham.

This last attribution is based on the similarity of the style between Simeon and Byrhtferth.

The last of Byrhtferth's works is an unsigned fragment of Old English text on computus in the Manuscript BL Cotton Caligula A.xv, fols. MS 142v-143r, attributed to him because of the stylistic similarity to the Old English that he wrote in Manual.

Byrhtferth has also been credited with Latin commentaries on Bede's De natura rerum and De temporum ratione (first attributed to him by John Herwagen) and a Vita S. Dunstani signed "B" (first attributed to him by Jean Mabillon).

However, many scholars argue that these works were not written by Byrhtferth, but instead were a compilation of material by several writers in the late ninth and early tenth centuries.

This is argued because of the smooth, polished style of these works in comparison with the styles of the only signed works Manual and Preface.

St. John's College, Oxford MS 17, contains several computistical works by Bede and Helperic, and a computus which includes the Latin Epilogus, or Preface, by Byrhtferth.

He also constructed a full-page diagram showing the harmony of the universe, and suggesting correspondences among cosmological, numerological, and physiological aspects of the world.

Other items in the manuscript may in fact be Byrhtferth, but it cannot be proved.

Also, he may have compiled most of these things from works that Abbo of Fleury left behind at Ramsey Abbey after his death.

Bodl. Ashmole MS 328 preserves Byrhtferth's Latin Enchiridion, or Manual.

It is written in Latin and Old English and the largest part is that of a computus similar to the one in Preface.

It touches on the belief that the divine order of the universe can be perceived through the study of numbers and can be of great reference for the study of medieval number symbolism.

It also contains treatises on rhetorical and grammatical subjects, a table of weights and measures and three theological tracts on the ages of the world, the loosing of Satan and the eight capital sins.