The Calendar and the Inscription Beneath It
The calendars encircling Leardo’s three maps constitute exceptional additions. Of these calendars, the one on the Society’s map is the most interesting. The inscription in the panel below the circles, in part an explanation of the calendar, is somewhat awkwardly phrased in the Venetian dialect of the fifteenth century, but, although it lacks the beginning of each line, the meaning is fairly clear, especially when certain of the missing lines are reconstructed from the corresponding inscription on the map in Vicenza.6
In the first two lines the cartographer makes an excursion into the realm of theology. According to Dr. Arthur C. McGiffert, to whom the present writer submitted the passage, this part of the inscription is “evidently not the work of a theologian, for it makes God the creator ‘of all things created and uncreated’ (the credal phrase is ‘things visible and invisible’), and in the next clause runs the Trinity (‘three persons and one common substance’) and the person of Christ together as if they were the same thing. There are reminiscences of the Nicene creed, but the whole is theologically a hodge-podge.”
This passage is followed by a statement that the map shows how the land and islands stand in relation to the seas and how the many provinces and mountains and principal rivers are distributed on the land. Then, on the asserted authority of Macrobius, “a very excellent astrologer and geometrician,” figures are given for the dimensions of the earth and of various heavenly bodies. These are quite fanciful, bearing little relation to the corresponding figures actually cited by Macrobius.7
The astronomical details are followed in the third paragraph by the explanation of the calendar. The latter consists of eight concentric circles, of which the innermost gives the dates of Easter for ninety-five years, from April 1, 1453, to April 10, 1547; when Easter falls in April, A is written in the small compartment, when in March, M; leap years are designated by B (“bissextile years”).
The second circle shows the names of the months, beginning with March, which was officially reckoned the first month of the year in the Republic of Venice until as late as 17978; it also tells the day, hour, and minute when the sun enters each of the twelve signs of the zodiac.
The third, fourth, fifth, and sixth circles enable one to calculate the phases of the moon. In the third circle the first nineteen letters of the alphabet represent in order the years of the Metonic lunisolar cycle. These years were usually designated by the golden numbers, but before the Gregorian reform letters were frequently employed in place of the numbers. Leardo explains that C stands for 1453, D for 1454, and so on until T is reached, after which we begin over again at A.9 A letter is placed opposite the figures (in the fourth, fifth, and sixth circles) showing respectively the day of the month, the hour of the day, and the “point of the hour” at which the “conjunction of the moon” (i. e. new moon) will take place in the years to which the letter refers. For example, there will be a new moon on April 8, 1453, at 16 hours, 200 points.10 Leardo adds that there are 1080 points in an hour.11
The seventh circle gives the dominical, or “Sunday,” letters; these are indicated opposite the days of the month (fourth circle) on which Sunday falls in the years designated by the seven first letters of the alphabet. If we know the dominical letter for any particular year, we may thus determine the days of the week.12 Leardo, however, does not specify the years to which the dominical letters in his calendar refer.
The eighth and ninth circles give the lengths of the days in hours and minutes.13 From this we see that the vernal equinox fell on March 11, inasmuch as the calendar was constructed before the Gregorian reform. Finally, in the tenth circle saints’ days and other religious festivals are shown.14
The four figures in the spaces between the calendar and the outer edge of the parchment represent the four evangelists: the lion for St. Mark, the bull for St. Luke, the angel for St. Matthew, and the eagle (of which only the head shows) for St. John.15
The Map Disk
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 Babylonians16) 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.
Medieval navigators’ charts also influenced Leardo. Towards the close of the thirteenth century sailors in the Mediterranean—particularly Italians and Catalans—began making marine maps (known as portolan charts) that far surpassed all earlier maps in the accurate delineation of coast lines. The majority of these show the Mediterranean and Atlantic coasts of Europe and of north Africa but little of the interior of the continents and nothing of the farther parts of Asia. Some, however, were used as the basis for maps of the world. On the latter the shore lines were derived from the navigators’ charts, and the remaining regions were compiled from other sources. The Leardo map belongs in this category.
Among the existing maps dating from the fourteenth and early fifteenth centuries our Leardo map is very closely related to the group of maps drawn by the famous Catalan cartographers of Majorca in the Balearic Islands. In its general outlines it is so strikingly like a Catalan map of about 1450 now preserved in the Este Library at Modena18 that we must assume a common cartographic ancestor at no great distance back. There are, however, certain legends on the Este map that Leardo does not give, particularly the long inscriptions and a multitude of place names on the Mediterranean and Atlantic coasts. Leardo’s map, on the other hand, has features not shown on the Este map. These are of two sorts: (1) place names in Asia and Africa, the counterparts of which may be found on other Catalan19 and Italian20 maps of the period; and (2) river, mountain, and province names taken directly from Ptolemy. There are also not a few names whose origins or counterparts on other maps I have been unable to trace.
Ptolemy’s Geography had been neglected during the earlier Middle Ages, but the enthusiastic interest in Greek literature which characterized the early Renaissance had led to its translation into Latin shortly before Leardo’s time.21 A strict interpretation of Ptolemy’s data would have necessitated a complete redrafting of the outlines of the continents, as was done on the Ptolemaic atlases of the mid- and late fifteenth century. Leardo made no such attempt. The extent of his concession to the Ptolemaic geography was to sprinkle a few of Ptolemy’s names over a medieval base and to add the Rivers Indus and Oechardes in eastern Asia.22
The Known World According to Leardo
The numbers in parentheses correspond to the reference numbers in the Appendix (pp. 32-60) and on the key maps at the end of the book.
In the Appendix (pp. 31-67) I have tried to identify as many as possible of the names and other features shown on the Leardo map with existing places, or at least with corresponding features on other maps of the period. Here I propose to conduct the reader on a rapid sight-seeing tour around the map, pointing out some of the most interesting details only.
Asia
In the extreme north (left-hand side) there is a large structure which looks like an Italian church with its campanile (13). The legend beneath, suggested ultimately by a passage from Marco Polo, runs about thus: “[This is] the sepulcher of the [Grand Khan] and they do this when he comes to be carried for interment: he comes accompanied by many armed men who kill those whom they find on the roads, and they say that the souls of these are blessed because they accompany the soul of the Grand Khan to another life.” Marco Polo adds that at the time of the funeral of Mangou Khan 20,000 persons were thus slain! The actual place of burial of the Mongol Khans was in Cathay, far away from northern Russia where Leardo, following the model of Catalan maps, draws it. European cartographers of the fourteenth and fifteenth centuries seem to have known and cared little about the relative positions of places in Asia; as Italian merchants by this time had established contacts with the Mongols in southern Russia, what was more natural than to place the Mongol overlord’s tomb in the hinterland of the Black Sea? Here there was more available space than in the Far East, and here on Leardo’s map the Grand Khan’s tomb could be made symmetrically to balance Prester John’s palace across the map in Africa (299).
South of the sepulcher we see the River Volga (6, 7) flowing into the northwestern corner of the Caspian (250). A branch from the east (8), perhaps the Kama, joins the Volga where the latter bends at a right angle to the south. East of the lower Volga is a “desert of thirty days” (10), Polo’s mysterious demon-haunted desert of Lop, where the traveler hears ringing bells and other uncanny sounds (possibly “singing sands”). Like the Grand Khan’s tomb, this desert is also wofully misplaced, since the actual desert of Lop lies in eastern Chinese Turkestan. The responsibility is not Leardo’s, however, for the Lop desert is in the same place on the Catalan Atlas of 1375 and on the Este map.
Farther east, beyond a row of six castles representing towns on the borderlands of China (35-40), we come to a gulf of the encircling ocean and to a great system of mountains. The gulf (11), which contains three islands, appears in almost the same position and form on the Este map, where there is a legend explaining that on the islands griffons and falcons are found and that the natives are not allowed to kill them without the permission of the Grand Khan of the Tatars. This is also from Marco Polo, who writes that the islands where the gerfalcons are bred lie so far north that the North Star is left behind you in the south! The mountains southeast of the gulf make an enclosure shaped something like a θ (42-47). Inside the northern half of this θ a legend tells us that “this is the province of Gog and Magog, where many tribes of the Jews were shut in” (70), referring to the medieval tradition that Alexander the Great enclosed Gog and Magog—the terrible hordes of Antichrist—within the Caspian Mountains. On many maps the mountains of Gog and Magog in the Far East are named thus. Leardo, however, places “Mo Gaspio” (Caspiae Montes) (4) north of the Caspian Sea somewhat nearer the position at which Ptolemy had placed them. To the mountains of Gog and Magog he assigns names derived from Ptolemy’s northeastern Asia. Running westward from the southern basin formed by these mountains Leardo has added a river (49), the Oechardes of Ptolemy. Near the point where this river emerges from the mountain rim we see a red spot labeled “Iron gate” (72) and, immediately to the west, two short red marks, “Statues of Alexander” (73). The iron gate was built by Alexander in the wall enclosing Gog and Magog, and the statues represent trumpeters set up by Alexander to keep guard over these unclean hordes. On the Catalan maps the trumpeters themselves are shown with their trumpets.
Immediately west of the statues appears “Mount Tanacomedo” (48), an amusing instance of Leardo’s carelessness; he has here evidently copied “Montana Comedorum” from a Ptolemaic map, combining the last part of the first word with the first part of the last! At the extreme eastern edge of the world disk we see the Terrestrial Paradise (63) surrounded by an enormous wall to keep out curious intruders. The River Indus flows southwestward to a great delta near the entrance of the Persian Gulf (84). Many of the place names in India correspond with those of the Catalan maps and in turn were derived from Marco Polo. The scene of St. Thomas’ mission and of the early introduction of Christianity into India is indicated by the inscription: “Here preached St. Thomas” (113).
In central Asia, we note two rivers entering the eastern side of the Caspian Sea, the Jaxartes (117) and Oxus (118). The Lake of Aral, in which these great streams actually have their outlet, seems to have been wholly unknown to the geographers both of antiquity and of medieval Europe. Moslem scholars, however, were aware of its existence. Leardo’s castles of Organa and of Organzia (Urganj) (120, 121) at the mouth of the Jaxartes and his place name Orcania (132) on the Oxus recall Matthew Arnold’s description of the Oxus at the close of Sohrab and Rustum:
But the majestic river floated on...
Right for the polar star, past Orgunjè,
Brimming, and bright, and large.
The Tigris and Euphrates (165, 166) join, reaching the Persian Gulf (267) as a single stream flowing between two large edifices that represent Susiana (172) and Babylonia (173). To the east of the Tigris a nameless river (139) having its headwaters in a large lake (138) also enters the Persian Gulf. This same stream on the Catalan Atlas and on the Este map rises in a double source, two bodies of water that have been identified with Lakes Van and Urmia. Leardo connects the Euphrates (166) with the Mediterranean through the Orontes (168) and with the Red Sea (268) through the Jordan (167).
The most prominent feature in Arabia is Mecca (211), a large domed and towered building in good Italian Renaissance style and presumably representing a mosque. Several corrupted Turkish place names (227, 228, 229, 232) along with classical names (224, 231, 233-235) appear in Asia Minor.
The Indian Ocean is filled with yellow and red islands. A legend asserting that pepper and spice are found in these islands (275) comes from Marco Polo’s description of the East Indian archipelago. The largest of all the islands, lying off the coast of India, is marked Taprobana (269) and probably represents Sumatra.
Africa
Leardo’s Africa, like that of the Este map, has a very unusual shape. Two gulfs reach inland from the Indian Ocean and from the Atlantic, partially cutting off the southern extremity of the continent. On the Este map the eastern gulf is not as prominent as that of Leardo’s map, but the western is even deeper. Kretschmer suggests that these features have sprung from a combination of the ancient doctrine of a vast austral continent with Ptolemy’s theory that the Indian Ocean is surrounded by land.23 Certain Arabic maps show an eastward projection of Africa like those of the Este map and Leardo, although they do not indicate anything corresponding to the western gulf.
Prester John’s castle (299) bulks large in the interior of Africa. In the twelfth century, reports spread through Europe of the vast realm of a fabulous Christian monarch in the heart of Asia. By the fourteenth century, however, Prester John’s empire had been transferred to Africa, where it became associated with the Christian kingdom of Abyssinia. The elaborate edifice with which Leardo represents Prester John’s empire may be intended for the sumptuous palace described in the thirteenth-century Letter of Prester John.
Like most medieval cartographers, Leardo makes the Nile (312) rise in West Africa (338). In this he follows Herodotus, Pliny, Mela, and other ancient authorities. Ptolemy, however, seems to have had a more correct view, placing the sources of the river in the Mountains of the Moon in eastern Africa. Nothing daunted, most of the fifteenth-century cartographers who used the writings of Ptolemy boldly transferred the Mountains of the Moon to West Africa to suit their theory of the river’s course. Thus, on the Leardo map we see the Montes Lunae (334) on the north coast of the West African gulf. Thence four streams flow north into a lake, out of which the Nile makes its way eastward and another stream flows westward into the Atlantic. The latter stream represents, perhaps, a combination of Niger and Senegal, of which some faint knowledge may have been gained through traders who had crossed the Sahara. The lower Nile is joined by the River “Stapus” (313), doubtless the Astapus of Ptolemy or the modern Blue Nile. On the Este map this tributary rises in the Terrestrial Paradise, there placed in East Africa.
To the mountain range of North Africa, the Carena of the Catalan maps, Leardo has added Ptolemaic names (385-392).
The Mediterranean
The outlines of the Mediterranean (433) and Black Seas (431) are more correct than any other features which Leardo draws. This, of course, is due to the fact that they were derived ultimately from the portolan charts. Leardo preserves the faulty orientation of the Mediterranean characteristic of the latter. If we assume that the perpendicular line extending from the wind-blower off the west coast of Spain through Jerusalem to the wind-blower east of the Terrestrial Paradise is intended to run due east and west, we see that the axis of the Mediterranean with the adjoining shores has been turned counter-clockwise some twelve degrees. This is probably because of failure on the part of the makers of the original portolan charts to take into consideration the declination of the compass.24
Leardo’s place names along the Mediterranean and Black Sea coasts are all derived from the portolan charts, although Leardo wrote names only where it was easy to do so without crowding. The least successful portion of Leardo’s Mediterranean coast is that of Spain: the shore is here unduly elongated as compared with that of the Este Catalan map, Barcelona (475) and Ampurias (476) being placed too far northeast on what ought to be the French shore line.
Europe
As on the Catalan maps, the geography of northwestern Europe is badly distorted. The Seine (448), Rhine (487), and Elbe (488) all flow parallel with one another but slightly to the south of west. The course of the Danube (552) with its southern branches is more true to nature. The Baltic Sea (577) and Scandinavia are drawn much as on the Este map.
Notes
1Giuseppe Crivellari, Alcuni cimeli della cartografia medievale esistenti a Verona, Florence, 1903, pp. 5-28.
2This map was discovered by Vincenzo Lazari in 1850. A detailed description and interpretation of it will be found in Santarem, Vol. 3, pp. 398-442 [fuller bibliographical details regarding this and other abbreviated references in these notes will be found on pp. 63-67]; black and white reproduction in Santarem’s Atlas, Part 3, No. 49; also in A. E. Nordenskiöld, Periplus, p. 61.
3The map was discovered in 1879 by Major Friedrich von Pilat, Imperial Counsellor of the Austro-Hungarian Legation and Consul-General of Austria-Hungary in Venice. At the time it was presented to the Society a brief anonymous description appeared in the Bulletin of the American Geographical Society, Vol. 38, 1906, pp. 365-368. This was based upon a sixteen-page pamphlet by Dr. Guglielmo Berchet, Il planisfero di Giovanni Leardo dell’ anno 1452, Venice, 1880, accompanying a photographic facsimile constituting No. XIV of the series Raccolta di mappamondi e carte nautiche del XIII al XVI secolo published by Ferdinand Ongania, Venice. Dr. Berchet’s paper, while useful to the present writer, has on the whole proved disappointing because of its many inaccuracies in transcriptions and also because almost no attempt was made to deal with the place names, in many respects the most interesting features of all.
4As much of this digit as remains might be the upper part of either a 2, a 3, or a 7. Since the Easter calendar begins with 1453 the date could hardly be earlier than Easter, 1452. For the same reason, it is not likely to have been as late as 1457, the only possible date after 1453. On the Vicenza Leardo map the Easter calendar begins with the year in which the map is dated, 1448; on the Verona map of 1442 the calendar begins with the preceding year, 1441. A discrepancy of four years between the beginning of the calendar and the date of the map, however, is most improbable.
Santarem, Vol. 3, p. 399, and Berchet, op. cit., p. 6, cite two mid-eighteenth century MSS in the Library of St. Mark’s, Venice, which contain entries relating to a map by Giovanni Leardo dated 1447. One of these MS is that of the Doge Marco Foscarini (Codex ital., XI, 123, p. 42), the other that of a contemporary scholar, Giovanni degli Agostini (Codex ital., VII, 291, p. 542; this and the preceding reference were furnished to the present writer by the Chief Librarian of the Library of St. Mark’s; they do not agree exactly with the references as given by Santarem and Berchet).
The passage from the Foscarini MS (Fig. 2) may be translated thus: “Gio. Leardo, who flourished in 1440, made a planisphere on parchment on which was written Leardius de Venetiis me fecit anno 1447. It was at the house of (era presso) Bernardo Trevisano. Apostolo Zeno saw it many times and marveled at seeing the exactness of the design.” The passage from the Agostini MS (Fig. 3) runs as follows: “Giovanni Leardo: This (man) lived shortly before the middle of the fifteenth century, and he delighted in geography and spheres. In the Trevisan Library was preserved a planisphere by him on parchment on which could be seen delineated the whole terraqueous globe with all the signs and celestial constellations, beneath which, according to his assertion, every part is placed. At the bottom of this parchment these words may be read: Joannes Leardius de Venetiis me fecit ab anno 1447. It is curious to see how in his time, when not many discoveries had been made and navigation was so little advanced, the positions of the provinces and of the seas were conceived.”
Berchet, op. cit., p. 7, points out that the arms at the top of the parchment of the Leardo map now belonging to the American Geographical Society are those of the Trevisan house. He reads incorrectly, however, the date given by Agostini as 1452, concluding therefrom that the map mentioned by the latter was the same as the Society’s map, the date of which he also reads as 1452. In view of the actual difference in the dates, we may conclude that Leardo constructed two maps for the Trevisan family, and that the one dated 1447 is yet to be rediscovered.
5Although the Society’s map is not, perhaps, one of the great, outstanding monuments of medieval cartography, the assertion of Theobald Fischer (Sammlung mittelalterlicher Welt-und Seekarten, Venice, 1886, p. 104) that the Leardo maps of 1448 and 1452 were “von geringem Wert,” seems too harsh.
6There follows a transcription of this legend. Missing passages supplied from the Vicenza map as transcribed on Santarem’s reproduction are given in square brackets:
... chreatore de Tute le Cose chreate et non chreato et E En 3 persone et una medexima sustanzia et uno Idio El quale En.i.inita (divinita?) E Incomprensibelle aiomeni et aianzelli quanti uisono dal zentro per sino Ala zirconferenzia En umanita... |... ene Maria et farsi homo pasibelle et sostener morte per Redimer Lumana zenerazione et resusito Il Terzo zorno et asexe... (en?) ziello ala destera del padre et al nouisimo di zudigera zusti et pechatori. Al nome de quel dio che cosi veramente chre... at|
... como La Tera et le Ixole stano nel mare et Molte prouinzie et monti et fiumi prenzipalli sono nela Tera El diamitro dela Tera sie meglia 6857 secondo Macobrio ezelentisimo Astrologo et geumetrico. El diamitro de Laqua| [sie meia 14796. El diametro de laiere sie m]eglia 31929¹/₇. E diamitro del fuoguo 68191²/₇. El diamitro de La Luna sie meglia 147149. El diamitro de mercurio sie meia 20(?)7533. El diamitro de venus sie meglia 692703. El diamitro del solle sie meia 1494781. El diamitro de mar(te) |... eia 6532374¹/₇ (Jupiter). El diamitro de saturno sie Meia 13997942⁴/₇. diamitrus horbis signiorum sie meia 29995591. diamitrus horbis aplanes sie meia 64276266⁵/₇. diamitrus horbis christalini sie meia 137724(?)856. pitagora dize che da La |....
[El primo zircholo che zirconscrisse Il sopra schri]to mapamondo sie de la raxon de la pasqua de la Rexurezione per Ani 95. Comenza nel 1453 adi primo aprille conpie nel 1547 adi 10 Aprille. quando si Troua nele caxelle Letera M aueremo La pasqua de marzo, quando si Trouera Letera A Aueremo| [quando la viene daprille. quando si troua letera B que]lano aueremo Bixestro. El segondo zircolo sie de I12 mexi dellano et quando Il sole Entra En cadauno dei 12 segni zelesti. El Terzo zircollo sie de 19 Letere de lalfabeto per Atrouar la raxon de La Luna. El quarto zircollo sie dei numeri (?)| [di zorni de mexi. El quinto sie de le ore.] El sesto zircollo sie Iponti de le hore. El setimo zircollo sie Le Letere dominicale. Lotauo zircollo sie Le ore de La grandeza del di En tututo (sic!) El tenpo de lano (?). El nono zircolo sie dei menudi che auanza oltra Le ore ne la grandeza del di. El dezim |... uoler sapere quando rinoua La Luna de Zugnio del 1453. nel dito mileximo Abiamo per letera concorente Letera C. Auoler atrouar La conioncion de la Luna dobiamo Atrouar Letera C nel mexe de zugnio E alincotro se trouera di.. |... (rin) ouera La Luna de cadauno mexe del dito mileximo. El mileximo comenz(a) de Zenaro nel 1454 aueremo concorente Letera d ecosi se schore ogniano 1 Letera de lalfabeto. Et quando sizunze aletera T l’Altro ano drieto sitorna Aletera A. |... raxone comenza Ala Leuar del solle e intendese atanti di et Atante hore et atanti (?) ponti. ponti 1080 sintende 1 hora. Ale fiade En uno mexe si troua 2 fiade una Letera en quel mexe La luna rinoua 2 fiade etc.
7By the “diameters” of the sun, moon, and planets Leardo obviously means the diameters of the orbits. Macrobius, Commentaria in somnium Scipionis, I, 20: 20, gives the diameter of the earth as 80,000 stades, which might, if converted into Arabic miles, be approximately the 6857 miles of Leardo. According to Macrobius the radius of the sun’s orbit is 4,800,000 stades (ibid., I, 20: 21); the diameter of the sun’s orbit would therefore be 9,600,000 stades, or 120 times that of the earth. The diameter of the sun’s orbit according to Leardo is 218 times that of the earth. On the authority of Porphyry, Macrobius (ibid., II, 3: 14) gives the relative distances between the planets; but Leardo’s figures bear no relation to these. I have not been able as yet to trace the origin of Leardo’s figures.
8H. Grotefend, Zeitrechnung des deutschen Mittelalters und der Neuzeit, Vol. 1, Hannover, 1891, p. 203 (reference kindly suggested by Dom Hugh G. Bévenot of Weingarten Abbey, Württemberg, Germany).
9Grotefend, op. cit., p. 113, asserts that O was usually omitted to avoid confusion with zero. Leardo, however, includes O. J and I are counted as one letter. The golden number of 1453 is 10; Leardo’s A corresponds with golden number 8.
10The following is a comparison of the times of the new moon on certain dates as indicated by Leardo with the actual times as determined for the meridian of Venice from Th. von Oppolzer, Canon der Finsternisse (constituting Denkschr. Kaiserl. Akad. der Wiss. in Wien, Math.-naturw. Classe, Vol. 52, 1887).
| Leardo’s Times | Actual Times | ||||
|---|---|---|---|---|---|
| 1453 | Dec. 1 | ? hrs. | 203? pts. | Nov. 30 | 2.40 P. M. |
| 1455 | Apr. 16 | 21 hrs. | ? | Apr. 17 | 12.22 A. M. |
| 1456 | Apr. 6 | 7 hrs. | 229 pts. | Apr. 5 | 4.25 A. M. |
| 1461 | Jan. 11 | 21 hrs. | ? | Jan. 11 | 8.44 P. M. |
| 1468 | Feb. 23 | 14 hrs. | 747 pts. | Feb. 23 | 10.15 P. M. |
The discrepancies are too great and too variable to enable us to come to any very definite conclusions as to the place or manner of origin of Leardo’s figures.
11The division of the hour into 1080 points (3×6×60, as Dom Bévenot points out) is puzzling. More usually the hour was subdivided into four points. See Grotefend, op. cit., p. 188.
12The dominical letter for 1453 was G.
13On the basis of certain of the figures given by Leardo for the lengths of the days at about the times of the solstices, I have estimated that this table was worked out for about lat. 42° 45′ N, which is more nearly the latitude of Orvieto than that of Venice (45° 30′). (This calculation was made with the Smithsonian Meteorological Tables, 4th edit. (constituting Smithsonian Misc. Colls., Vol. 69, No. 1), Washington, 1918: Table 87, “Duration of Sunshine at Different Latitudes,” and Table 88, “Declination of the Sun for the Year 1899.” The difference in the declination of the sun for 1452 and 1899 is negligible.) Dom Bévenot writes: “I fancy day lengths were reckoned roughly for degrees. Here in Weingarten about 1490 they used tables drawn up for lat. 45° N, though the place is actually 47° 40′.”
14I am indebted to Dom Bévenot for the following comment:
“Concerning the calendar of saints I find the good Venetian has inserted besides the usual feast of St. Mark, patron of Venice, on April 25 two more: that of his apparition and the finding of his relics on June 25 and a third feast on Jan. 31 (translation). The last two were special for the diocese of Venice (Aquileia). The calendar for Aquileia is given at the beginning of Grotefend, op. cit., Vol. 1, but does not quite tally with Leardo’s list of saints. Perhaps this is because Grotefend has modernized the calendar. It may be that Leardo, living perhaps elsewhere than in Venice or its diocese, put in feasts that were dear to him. Indeed, in view of your findings for latitude from the length of the days [see preceding note], Rome is the most likely place, perhaps, for the Venetian embassy. It lies nearly in lat. 42° N; if we allow for Leardo measuring the length of the days according to the apparent sunset and sunrise, this may well explain a discrepancy of the greater part of a degree.”
15Berchet, op. cit., p. 7.
16See H. F. Lutz, Geographical Studies Among Babylonians and Egyptians, in Amer. Anthropologist, Vol. 26 (N.S.), 1924, pp. 160-174.
17See Appendix, Nos. 305, 619.
18Kretschmer, CE see p. 63.
19Particularly the famous Catalan Atlas of 1375 see p. 63.
20For the names of and for bibliographical references relating to some of these maps see the list of references on pp. 63-67, sub CD, Mauro, Piz., Vat., Vilad.
21This Latin translation of Ptolemy’s Geography was begun by the Byzantine scholar Emmanuel Chrysoloras and completed by Jacopus Angelus in 1410; manuscripts of this translation were accompanied by maps, which, however, differ from the well-known maps in the Ptolemaic atlases of the late fifteenth and sixteenth centuries. The latter were the work of Dominus Nicolaus Germanus, known as Nicholas Donis. See A. E. Nordenskiöld, Facsimile Atlas to the Early History of Cartography, transl. by J. A. Ekelöf and Clements R. Markham, Stockholm, 1889, pp. 9-10.
22Like the Leardo map of 1452, the map of Walsperger, 1448, reveals Ptolemaic influence in some of its names although all the topographical features are strictly medieval. The Genoese world map of 1447 in its elliptical form is the result of a more serious attempt to reconcile the Ptolemaic geography with the traditional views. See Kretschmer, CE, pp. 76-77; on the Walsperger map, Kretschmer, Eine neue mittelalterliche Weltkarte der vatikanischen Bibliothek, in Zeitschr. Gesell. für Erdkunde zu Berlin, Vol. 26, 1891, pp. 371-406, reference on pp. 376-377. On the Genoese world map see the extended commentary of Fischer, op. cit., pp. 155-206.
23Kret., CE pp. 82-83.
24See Kret., Port., pp. 81-93; see also E. L. Stevenson, Portolan Charts: Their Origin and Characteristics, with a Descriptive List of those Belonging to the Hispanic Society of America, New York, 1911, p. 19, where it is suggested that the faulty orientation of the Mediterranean may be in part connected with the persistence since the time of Ptolemy of the practice of placing Constantinople on maps “too far to the north by at least two degrees.”