[139] See Muntz, _Les Peintres d'Avignon_, 1342-1352, Tours, 1885; and _Les peintures de Simone Martini à Avignon_, Paris, 1885. Many of these paintings still exist in a good state of preservation, especially those on the vault of the small private chapel of the Popes. [140] This subject is discussed at greater length in Chapter XIII. [141] See page 206 on the favourable conditions under which the monastic illuminators did their work. [142] _Books of Hours_ were the prayer-books of the laity, as the _breviary_, _portiforium_, or "_portoos_" was the prayer-book of the priest. [143] See below, page 230, for an explanation of the difference between "mat" gold applied as a fluid pigment with a brush, and burnished gold leaf laid over a raised "mordant" or enamel-like ground. [144] In point of technique these beautiful miniatures are exactly like very delicate wood-cuts, though in most cases they appear to have been cut (in relief) on blocks of soft metal, treated just as if it had been wood. [145] Perhaps the earliest was one issued in 1486 by Antoine Verard. [146] In these earliest Parisian printed _Horae_ the backgrounds of the borders are left plain white; unlike the later ones, in which the borders have dotted or _criblée_ backgrounds. [147] They include many different _uses_, especially that of Paris, Rome, Rouen and Sarum. [148] Both Verard and Pigouchet produced _Horae_ for the publisher Simon Vostre. [149] It is incorrect to speak of _editions_ of these _Books of Hours_; hardly any two copies appear to have been quite the same; fresh arrangements and combinations of a large stock of engraved blocks were made for the printing of almost every copy, and thus the long list given by Brunet is very incomplete; see the last volume of Brunet's _Manuel du libraire_, Paris, 1865. [150] Sold in June, 1873, for £181, with the rest of the Perkins library. [151] A copy of this glory of the printer's art in Mr Quaritch's possession is priced in his catalogue of 1891 at £5250; only eight copies are known to exist. [152] In 1449 Schoeffer was a young illuminator of manuscripts residing in Paris. [153] Mentelin was enrolled as an illuminator in the Painters' Guild at Strasburg in 1447; and Colard Mansion, Caxton's master in the art of typography, belonged, as a scribe and illuminator, to the Guild of St John and St Luke at Bruges. In 1471 he was elected Warden or _Doyen_ of his Guild.