The outlines of several medieval maps resemble each other to such an extent that there can be no doubt that they are derived from the same original source. This source by some authors is assumed to have been the official map of the Roman Empire, but if we compare the crude outline given to the Mediterranean with the more correct delineation of Ptolemy, who was certainly in a position to avail himself of these official sources, such an assumption is untenable. The earliest delineation of the description has already been referred to as the Anglo-Saxon map of the world. Next in the order of age, follows the oval map which Henry, canon of Mayence Cathedral, dedicated to Mathilda, consort of the emperor Henry V. (1110). Of far greater importance is the map seen in Hereford Cathedral. It is the work of Richard of Haldingham, and has a diameter of 134 cm. (53 ins.). The "survey" ordered by Julius Caesar is referred to in the legend, evidently derived from the Cosmography of Aethicus a work widely read at the time, but this does not prove that the author was able to avail himself of a map based upon that survey. A map essentially identical with that of Hereford, but larger--its diameter is 15.6 cm. (6 in.), and consequently fuller of information--was discovered in 1830 in the old monastery of Ebstorf in Hanover. Its date is 1484. Both maps abound in miniature pictures of towns, animals, fabulous beings and other subjects. The Hereford map is surmounted by a picture of the Day of Judgment. Similar in design, though much smaller of scale and oval in form, are the maps which illustrate the popular _Polychronicon_ of Ranulf Higden, a monk of St Werburgh's Abbey of Chester (d. 1363). [Illustration: FIG. 11.--The Hereford Map (c. 1280).] [Illustration: FIG. 12.--The Map of Beatus (776).] Pomponius Mela tells us that beyond the Ethiopian Ocean which sweeps round Africa in the south and the uninhabitable torrid zone, there lies an _alter orbis_, or fourth part of the world inhabited by _Antichthones_. On a diagram illustrating the origines of Isidore of Seville (d. 636) this country is shown, but is described as a _terra inhabitabilis_. It is shown likewise upon a number of maps which illustrate the _Commentaries on the Apocalypse_, by Beatus, a Benedictine monk of the abbey of Valcavado at the foot of the hills of Liebana in Asturia (776).