This place and period remind me, that before I pass on to another epoch, I ought to say a few words concerning the invention of painting on glass, which was anciently likewise styled Mosaic, because it was composed of pieces of different coloured glass, connected by lead, which represented the shadows. We may observe glass windows that emulate well composed pictures on canvass or on panel; and this art is treated of by Vasari in the thirty-second chapter of the introduction to his work. From the preface to the treatise _De omni scientiâ artis pingendi_, by Theophilus the Monk, I find that France was celebrated for this art beyond any other country;[177] and there the art seems to have been invariably cultivated, and brought by degrees to perfection. From the earliest ages of the revival of painting, the Italians wrought windows with different coloured glasses, as is remarked by P. Angeli in his description of the churches of Assisi, where the most ancient specimens are to be seen. In the church likewise of the Franciscan friars at Venice, we find that one _Frater Theotonius_, a German, worked in tapestry and glass windows, and was imitated by one Marco, a painter, who lived in the year 1335.[178] It may also be observed, that such windows over the altars supplied the place of sacred paintings in churches; Christian congregations, in lifting up their eyes, there sought the resemblance of what "they hoped some time to behold in the celestial paradise: che ancor lassù nel ciel vedere spera," and they often addressed their supplications to those images. In the fifteenth century Lorenzo Ghiberti, a man eminent in various arts, still further improved this, and ornamented the oval windows of the façade of the church of S. Francis, and of the cathedral of Florence with coloured glass. In a similar manner he finished all the oval apertures in the cupola of the cathedral, except that of the Assumption, executed by Donatello. The glass was manufactured at Florence, for which purpose one Domenico Livi, a native of Gambassi, in the principality of Volterra, who had learnt and practised the art at Lubec, was invited to that place, as is proved by Baldinucci in his correction of Vasari.[179] From this school apparently came Goro, and Bernardo di Francesco, with that train of Ingesuati, whose workmanship, exhibited at S. Lorenzo and elsewhere, has been much commended by the Florentine historians. (See Moreni, part vi. p. 41.) This art afterwards flourished at Arezzo, where it was introduced by Parri Spinelli, a scholar of Ghiberti. About the same time flourished in Perugia P. D. Francesco, a monk of Cassino, not merely a painter in glass, but a master in that city; and some conjecture that Vannucci profited by his school, though a comparison of dates does not much favour such a supposition. This art also flourished in Venice, about 1473, where one window was executed after the design of Bartolommeo Vivarini, in the church of S. John and S. Paul, and another