Nearly two thousand actual rolls were discovered at Herculaneum, of course in a highly-carbonized condition, and of them some hundreds have been unrolled. None appear to have been embellished with illumination;[3] so that for proof of the practice of the art in classical times, we are thrown back upon the classical authors themselves. The allusions in their writings to the employment of red and black ink are frequent. Martial, in his first epistle, points out the bookseller's shop opposite the Julian Forum, in which his works may be obtained "smoothed with pumice-stone and decorated with purple." Seneca mentions books ornamented "cum imaginibus." Varro is related by Pliny to have illustrated his works by likenesses of more than seven hundred illustrious persons. Pliny again informs us that writers on medicine gave representations in their treatises of the plants which they described. Martial dwells on the editions of Virgil, with his portrait as a frontispiece. The earliest recorded instance of the richer adornments of golden lettering on purple or rose-stained vellum, is given by Julius Capitolinus in his life of the Emperor Maximinus the younger. He therein mentions that the mother of the emperor presented to him, on his return to his tutor (early in the 3rd century), a copy of the works of Homer, written in gold upon purple vellum. Whether derived from Egypt or the East, this luxurious mode of embellishment appears to have been popular among the later Greeks, a class of whose scribes were denominated "writers in gold." From Greece it was, no doubt, transplanted to Rome, where, from about the 2nd century, it, at first slowly, and ultimately rapidly, acquired popularity. St. Jerome, indeed, writing in the 4th century, in a well-known passage in his preface to the Book of Job, exclaims:--"Habeant qui volunt veteres libros vel in membranis purpureis auro argentoque descriptos vel uncialibus, ut vulgo aiunt, literis, onera magis exarata quam codices; dummodo mihi meisque permittant pauperes habere scedulas, et non tam pulchros codices quam emendatos."[4]