by numerous designs by which one thread can be traced through curious knots and complications, which, disposed over large surfaces, balance one another, but always with special varieties and arrangements difficult to trace with the eye. The long thread appears and disappears without breach of continuity, the two ends generally worked into the head and the tail of a serpent or a monster. The reliquary containing the "Bell of Saint Patrick" is covered with knotted work in many varieties. A two-handled chalice, called the "Ardagh Chalice" found near Limerick in 1868, is ornamented with work of this kind of extraordinary fineness. Twelve plaques on a band round the body of the vase, plaques on each handle and round the foot of the vase have a series of different designs of characteristic patterns, in fine filigree wire work wrought on the front of the repoussé ground. Much of the medieval jewel work all over Europe down to the 15th century, on reliquaries, crosses, croziers, and other ecclesiastical goldsmiths' work, is set off with bosses and borders of filigree. Filigree work in silver was practised by the Moors of Spain during the Middle Ages with great skill, and was introduced by them and established all over the Iberian Peninsula, hence it was carried to the Spanish colonies in America. The manufacture spread over the Balearic Islands, and among the populations that border the Mediterranean. It is still made all over Italy, and in Portugal, Malta, North Macedonia, Albania, the Ionian Islands and many other parts of Greece. That of the Greeks is sometimes on a large scale, with several thicknesses of wires alternating with larger and smaller bosses and beads, sometimes set with turquoises, and mounted on convex plates, making rich ornamental headpieces, belts, and breast ornaments. Filigree silver buttons of wire-work and small bosses are worn by the peasants in most of the countries that produce this kind of jewellery. Silver filigree brooches and buttons are also made in Denmark, Norway, and Sweden. Little chains and pendants are added to much of this northern work. Iberian Peninsula The oldest filigree pieces discovered in the Iberian Peninsula date back to 2000–2500 BC, but its origin is not clear. These pieces possibly belonged to merchants and navigators originally from the Middle East and are not thought to have been produced in the region at that time. Filigree began to be produced in Portugal