It should be noted first that east is at the top of the map and Jerusalem at the center; hence the long axis of the Mediterranean runs vertically up the southern half of the disk.
With the exception of the Red Sea, appropriately colored, the seas are uniformly blue. The lands are left the natural color of the bleached parchment except for a fiery red region in the far south bearing the legend: “Desert uninhabited because of heat,” and a dreary brown waste in the far north marked: “Desert uninhabited because of cold.” Islands are tinted either red or yellow, with green patches in the interior of Great Britain and Ireland. The only other natural features depicted are mountains, rivers, and lakes, although certain deserts are mentioned in legends. Mountain ranges are represented by rows of mounds, alternately red, green, and blue, and each rising symmetrically in two or three steps. Rivers are blue and, as frequently on medieval maps, sometimes connect one sea with another, or at least have common sources. A yellow lake, labeled “Sandy Sea,” lies in the midst of the Sahara.
Vignettes of castles, walled towns, and churches stand for cities, kingdoms, and regions. In most cases the names have been written upon the vignettes themselves; since the latter are also colored pink or green, the letters are frequently obscured and quite illegible. Many towns and districts are shown by red dots beside which the names are written in ink, once black but now faded with age. These names were inserted after the vignettes were drawn, for in many instances they are tilted or compressed to fit the available space. The draftsman did not venture to write any name to the left of the dot to which it belongs; as he could not write on the blue of the seas, he was obliged to invert the map in the case of places on south-facing coasts. Names of islands and seas, which had to be written on water surfaces, are inclosed in small yellow panels. The names of the continents, the two inscriptions relating to the polar and equatorial deserts, and the words “Terrestrial Paradise” are in red capitals; but all other names are in minuscule, usually without an initial capital. Besides place names there are a few longer legends.
Winds blowing from the four cardinal and four intermediate points of the compass are shown by eight faces around the edge of the disk. Those to the north, northwest, and northeast are blue, suggesting cold blasts from these quarters; the other faces are ruddy.
Although decorative, the Leardo map lacks many of the pictorial elements—animals, birds, preposterous monsters—that enliven the blank spaces on other medieval maps. With the exception of the eight wind faces and the symbolic figures of the evangelists no living creatures, whether animals or men, are graphically represented.
Sources of Leardo’s Geography
Briefly stated, the sources of Leardo’s geography are to be sought in the information accumulated by the Greeks and Romans, as added to and altered during the early Middle Ages by the Church Fathers on the basis of the interpretation of the Bible and as later augmented by the work of medieval travelers, merchants, and sailors.
At a very early period the Greeks developed the idea (borrowed, perhaps, from the Babylonians[16]) that the earth is a flat disk surrounded by the Ocean Stream. This conception seems to have given rise to a cartographic tradition followed by certain ancient and medieval map-makers who had long outgrown the belief that the earth is actually flat. Thus Leardo draws a circular land mass, or oikoumene, surrounded by a narrow hem of water. We cannot, however, question his belief in the sphericity of the earth, for otherwise he could hardly have held the views expressed in the panel below the calendar. Furthermore, his two legends relating to the fiery and frozen deserts echo a theory that was propounded in classical times and based on the hypothesis of a spherical earth. This theory, worked out in detail by Crates of Mallos, is briefly as follows.[17] Around the equatorial circumference of the globe is a fiery zone so intensely hot that no man can cross it. This zone cuts off all communication with the southern hemisphere. The north and south polar caps are uninhabitable because of the cold. An ocean encircling the globe from north to south intercepts communication with the half of the northern hemisphere opposite the oikoumene. Many maps were made in the Middle Ages to illustrate this conception. Leardo presumably had it in mind and did not intend to represent either a flat disk or a complete hemisphere but merely a circular portion of the earth’s surface lying north of the equator.
In its orientation, with east and the Terrestrial Paradise at the top and with Jerusalem at the center, the map follows the Christian tradition of the earlier Middle Ages. Other features reflecting the influence of the Scriptures are Noah’s Ark resting on top of Mt. Ararat, Mt. Sinai, the exaggerated length of the River Jordan, and an inscription in the far northeast referring to Gog and Magog.
Later medieval contacts between Europe and remote lands are revealed in names derived from Marco Polo and possibly from other Western travelers who had visited the Orient, as well as in the Arabic names in Asia and Africa.