Claude Buy de Mornas (d.1783) was a professor of geography and history and became geographer to the Duc de Berry and to the King. This extremely decorative atlas is a complete scientific body of work in four volumes. The first volume entitled ‘Atlas Methodique et Elementaire de Geographie et d’Histoire’ published in 1761 encompasses the physical structure of the earth and its place in the solar system, the development of cosmography and lays the foundation of the human world at the time. It is illustrated with numerous double page plates of maps, charts and tables each set within a very ornate engraved frame. Volumes two to four were published the following year and bear the title ‘Atlas Historique et Geographique’ focuses on historical geography and is illustrated in a similar attractive style. The volumes were sold individually and are often found that way. A complete matching set in the first edition is scarce. A fifth volume was announced but was never apparently published. Brunet states ‘Cet ouvrage, commencé sur un plan trop vaste, n’a pas été terminé; on y trouve quelquefois joint un 5e ol. Qui n’est autre chose que le mauvais atlas unersel publié par Desnos’. However in the same year 1762 Rigobert Bonne’s ‘Atlas Moderne’ was published which fits nicely into this scheme and is of a similar size. There is no other obvious link between the two. The ensuing edition by Desnos in 1783 lacked the ornamental borders but stated at the foot of the title page that the intended work of was to be composed of 5 volumes with 332 plates. Volume one on cosmography contained 57 plates, followed by three volumes of ancient geography with 209 plates. The fifth volume of modern geography was composed of 60 plates (Phillips states 66). The ABPC records only two complete examples in nearly 40 years at auction. Brunet III p. 1910; Phillips (1909-) no. 628; Refer Shirley (2004) T.Buy 1a & 2a (lacking one volume).