However, such work was obviously false, while there have been some very clever imitations engraved on very fine gems. The famous Poniatowski Collection was the greatest of the gigantic frauds of the sort perpetrated. In the happier days of the First Empire the patronage of the Empress Josephine had brought appreciation of the glyptic art to a pinnacle, whence it fell from mere discouragement by the exposition of the Poniatowski Collection fraud in a London market. These gems might best be described as regular pictures in stone and portraits of all the celebrated men of antiquity, each blandly “authenticated” with his proper name and the artist’s signature! No wonder collectors and amateurs turned, frightened, to scan their own collections. If such traffic was fostered by dealers of their time, what recourse had they outside careful and arduous scholarship? Still, minute rudimentary knowledge of gem-engraving and its chronological phases should at once have set them at ease. The amateur of to-day knows that a signed gem is an exception to the rule and rests secure in the knowledge. Although the various periods of Greek glyptic art have been indicated, it may be helpful to repeat them here in tabulated form, following mainly Walter’s scheme of classification. I Prehistoric Period--2500 to 900 B.C. Primitive seal stones, imported cylinders. II Early Period--900 to 600 B.C. Island gems. Mycenæan era. III Archaic Period--600 to 500 B.C. Scaraboids supersede scarabs. IV Transitional Period--500 to 450 B.C. Finely engraved gems and prevalence of genre subjects. V Culminating Period--450 to 400 B.C. Perfection in engraved gems. Greek gems of the latest period are rare in comparison with those of periods preceding and following. That Greek influence reached Etruria has been shown by full evidence in many ways, and we have large numbers of engraved gems from Etruscan tombs of the fifth and fourth centuries, these intaglii having for their subjects most commonly incidents from legends of the Greek heroes. It is well to note that deities are rarely portrayed on Etruscan gems, whose form was usually that of the scarab. The fourth century finds their workmanship greatly deteriorating. The Romans were very fond of engraved gems and practised the glyptic art from early times. When Constantine the Great removed the seat of the Roman Empire to Constantinople in 329 A.D. this art, like the other arts, followed him thither, of course; but for over a thousand years succeeding the intaglii produced seldom attained great excellence and the taste for engraved gems followed other esthetic tendencies into the obscure retirement of the dark ages. In fact, the glyptic art almost became extinct, but with the expulsion of the Greeks from Constantinople by Mahomet in 1453 A.D. it found itself again on Italian soil, thereafter to grow strong and flourish from the root it had taken.