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Byfium, a fine thready matter produced in India, Egypt, and about Elis in Achaia, of which the richest apparel was anciently made, especially that worn by the priests both Jewish and Egyptian. Some interpreters render the Greek Burov, which occurs both in the Old and New Testament, by fine linen. But other versions, as Calvin's, and the Spanish printed at Venice in 1556, explain the word by silk; and yet byfius must have been different from our silk, as appears from a multitude of ancient writers, and particularly from Jul. Pollux. M. Simon, who renders the word by fine linen, adds a note to explain it; viz. that there was a fine kind of linen very dear, which the great lords alone wore in this country as well as in Egypt." This account agrees perfectly well with that given by Hesychius, as well as what is observed by Bochart, that the byfius was a finer kind of linen, which was frequently dyed of a purple colour. Some authors will have the byfius to be the same with our cotton; others take it for the linum afhefium; and others for the lock or bunch of silky hair found adhering to the pinna marina, by which it fastens itself to the neighbouring bodies. Authors usually distinguish two sorts of byfius; that of Elis; and that of Judæa, which Byzantium, which was the finest. Of this latter were the priestly ornaments made. Bonfrerius notes, that there must have been two sorts of byssus, one finer than ordinary, by reason there are two Hebrew words used in Scripture to denote byssus; one of which is always used in speaking of the habit of the priests, and the other of that of the Levites.

**Bryssus Ajboflinus**, a species of asbestos or incombustible flax, composed of fine flexible fibres, parallel to one another. It is found plentifully in Sweden, either white, or of different shades of green. At a copper mine in Westmanland it forms the greatest part of the vein out of which the ore is dug; and by the heat of the furnace which melts the metal, is changed into a pure semitransparent flag or glass.