My info to the text says, anonymous ca. 1410-1420, Vatican library, but the text appears to be from Albricus, called Albricus or Albericus Londonensis or Philosophicus, somehow 13th century.
http://books.google.com/books?id=YOISgW ... us&f=false
... here assumed to be possibly identical with Alexander Nequam.
Similar pictures appear as illustrations to the work of Evrart de Conty and his very large comment (ca. 1398) to an anonymous poem "echecs amoureux" (ca. 1370) in editions, from which the oldest surviving seems to be from 1467 (Burgund).
See our collection:
The clouds were typical for the second Urbino manuscript, as already discussed, and the author of the E-series only used them for Geometria. This manuscript is given with ca. 1470, what could mean much, but it seems probable (from my perspective), that the pictures arrived Urbino with Lazzarelli's other pictures and that not before end of 1474 and probably a little later. I would assume, that Lazzarelli's pictures had "clouds".The figure on the medal, except for the wings, seems quite similar indeed, as though the "Mantegna" card had been a model, as to be sure they were in numerous places over the next decades. The artist made a few improvements: more majestic wings, and a suitable cloud for her to float on (to that extent like the Urbino image). I can't imagine that the medal was a model for the "Mantegna" image, because the cloud is a touch the "Mantegna" artist would probably not have been able to resist. As it is, he only gives Geometry a cloud, of a rather different sort, too. Are those balls inside the sphere the seven planets, or what? That part is different, too.
But Sweynheim probably already had pictures (possibly ready engravings), to this themes, as he also could offer ready engravings for the 4 cardinal virtues. So the e-series redaction decided partly for the Lazzarelli motifs and partly for the Sweynheim motifs. Although, this interpretation hampers with the condition, that most of the artes liberalis pictures are similar in gesture and attributes. Perhaps it is explained by the condition, that the duke Montefeltro himself couldn't interfere in the production of the Lazzarelli manuscript, which possibly was an indirect gift from the pope Sixtus, but found reason to have altered motifs for the other editions.
By these considerations we should face the condition, that Sixtus (or his nephew, the later Pope Julius II, who gave the commission to Pollaiuolo) for his personal graveyard monument took the liberal arts and virtues as motifs.
The top plates shows six virtues, not the artes liberales, which somehow are presented at the lower border (would be nice to know these pictures, if you find them). The virtues are sitting, similar to the artes liberales in the Urbino manuscript.
Sixtus had two sides, one the better and the other bad. His good side saw many buildings and positive activities in Rome, the bad side is representative for his eagerness to develop a mighty Riario/Rovere family. This connects to his 3 major nephews, from which the first great protege died by his many festivities in 1474, after which the other two, Girolamo (husband to Catherina Sforza) and the later pope Julius, competed on some even level with each other till ca. 1476/77, and then was following a preference for Girolamo's worldly interests, which led to murder in Florence in 1478 and to the Ferrarese war 1482-84 and to an increasing chaos in Rome.
When the later Julius commissioned the tomb of Sixtus, he naturally connected to the time, when he himself stood a at the brighter side of life, so the period of 1474-76. Then Julius had a close, somehow mysterious connection to Lorenzo Zane, whom he wished to become a cardinal, and when this didn't work as he considered, then Julius reacted remarking emotional and risking all and everything in a furious rage about this misfortune in a seemingly not so important matter. In his later time as pope he had been occasional comparable furious and emotional, so it might simply a reason of an unusual choleric temperament, but also it might well be, that the relation between Zane and Julius had a rather dark mystery, especially as Zane was then already known as a trouble maker.
Some time later Zane changed sides from Julius to Girolamo and Julius was accused of an murder attempt on Girolamo with Zane as a witness, who wasn't allowed to be punished himself. A very dark story, possibly only staged by Girolamo to cause Julius having bad credit at the side of Sixtus.
Nonetheless, at the tomb of Sixtus, commissioned ca. 1489 (that is one year after Girolamo was murdered in Forli), Julius presented Sixtus with virtues and artes liberales, motifs, which also appear in the Mantegna Tarocchi, which according Trionfi.com's theory was made ca. 1475 in the good phase of the relation between Julius and Sixtus.
In the conclave 1492 Julius became the French candidate and had some chances, but Borgia decided the matter by a lot of money.
The intellectual side of Sixtus IV:
Sixtus in the library
Ground-plan of part of the Vatican Palace, shewing the building of Nicholas V., as arranged for library purposes by Sixtus IV., and its relation to the surrounding structures. From Letarouilly, Le Vatican, fol. Paris, 1882; as reproduced by M. Fabre.
http://www.gutenberg.org/files/26378/26 ... .htm#fig97
"Thanks to the care with which Platina set down his expenditure, we are able to follow step by step the gradual transformation of the rooms. His account-books, begun 30 June 1475, record, with a minuteness as rare as it is valuable, his transactions with the different artists and workmen whom he thought proper to employ. It was evidently intended that the library should be beautiful as well as useful, and some of the most celebrated artists of the day were set to work upon it."
Thanks to the care with which Platina set down his expenditure, we are able to follow step by step the gradual transformation of the rooms. His account-books, begun 30 June 1475, record, with a minuteness as rare as it is valuable, his transactions with the different artists and workmen whom he thought proper to employ. It was evidently intended that the library should be beautiful as well as useful, and some of the most celebrated artists of the day were set to work upon it.
The librarian prudently began in August, 1475, by increasing the light, and a new window was made "on the side next the court." It seems to have been impossible to get either workmen or materials in Rome; both were supplied from a distance. For the windows, glass, lead and solder were brought from Venice, and a German, called simply Hormannus, i.e. Hermann, was hired to glaze them. For the internal decoration two well-known Florentine artists—the brothers Ghirlandajo—were engaged, with Melozzo da Forli, who was painting there in 1477. In 1476 the principal entrance was decorated with special care. Marble was bought for the doorcase, and the door itself was studded with 95 bronze nails, which were gilt, as were also the ring and knocker, and the frame of trellised ironwork (cancellus), which hung within the outer door.
The building is entered from the Cortile del Papagallo through a marble doorway (fig. 98, A) in the classical style surmounted by the arms of Sixtus IV. On the frieze are the words sixtus papa iiii. The doorcase is doubtless that made in 1476; but the door, with its gilt nails and other adornments, has disappeared. Within the doorway there has been a descent of three steps at least to the floor of the Library. The four rooms of which it was once composed are now used as the Floreria or Garde-meuble of the Vatican Palace; a use to which they have probably been put ever since the new Library was built at the end of the sixteenth century.
The Latin Library, into which the door from the court opens directly, is a noble room, 58 ft. 9 in. long, 34 ft. 8 in. wide, and about 16 ft. high to the spring of the vault. In the centre is a square pier, which carries the four plain quadripartite vaults, probably of brick, covered with plaster. The room is at present lighted by two windows (B, C) in the north wall, and by another, of smaller size, above the door of entrance (A). That this latter window was inserted by Sixtus IV., is proved by the presence of his arms above it on a stone shield. This is probably the window "next the court" made in 1475. The windows in the north wall are about 8 ft. high by 5 ft. broad, and their sills are 7 ft. above the floor of the room. Further, there were two windows in the west wall (b, c) a little smaller than those in the north wall, and placed at a much lower level, only a few feet above the floor. These were blocked when the Torre Borgia was built by Alexander VI. (1492-1503), but their position can still be easily made out. This room must have been admirably lighted in former days.
The room next to this, the Greek Library, is 28 ft. broad by 34 ft. 6 in. long. It is lighted by a window (fig. 98, D) in the north wall, of the same size as those of the Latin Library, and by another (ibid., E) a good deal smaller, opposite to it. This room was originally entered from the Latin Library by a door close to the north wall (d). But, in 1480, two large openings (e, f) were made in the partition-wall, either because the light was found to be deficient, or because it was thought best to throw the two rooms into one as far as possible. At some subsequent date the door (d) was blocked up, and the opening next to it (e) was carried down to the ground, so as to do duty as a door. The other opening (f), about 7 ft. 6 in. square, remains as constructed.
The famous library picture with Platina, Sixtus, Girolamo, Giuliano (= Julius) and two other nephews.
Sixtus, walking with the time (the expanding printing press productions in 1475) showed scientific (university) interests.