The matrass, sometimes called a bolthead, especially where its neck was drawn out unusually long, was among the most common vessels on an alchemist's bench, used interchangeably as a sealed digester and, fitted with a head, as a distilling flask. The word's origin is not fully settled: one plausible line connects it to the French materas or matelas, the bolt fired from a crossbow, the source of the alternate name bolthead, while another traces it to Arabic matra, a leather bottle; either way, the matrass and the bolthead are documented as names for the same round-bodied, long-necked shape rather than as two separate vessels, and treating them as identical here reflects that record rather than manufacturing a distinction between them.
The matrass's basic shape did not vanish with alchemy; it passed directly into early modern and modern chemistry as the Florence flask, a round-bottomed flask with a long neck used for boiling and distilling, which occupies essentially the same role on a chemistry bench today that the matrass occupied on an alchemist's. That continuity of shape, more than any single named inventor, is the real story this vessel has to tell: a simple round body and a long neck proved useful enough, across a thousand years of glassblowing, that nobody ever found a strong reason to redesign it from the ground up.