(Theodore), a famous physician of the 17th century, was born at Amsterdam, and acquired a great reputation by his discoveries and his works. works. He found out the secret of softening amber without depriving it of its transparency; and made use of it in covering the bodies of curious insects, in order to preserve them. He was a member of the Royal Society of London; and died in 1693 at Hamburg, where he had spent the greatest part of his life, with the title of resident of the grand duke of Tuscany. His principal works are, 1. Spicilegus anatomicus. 2. Anthropogenia ichnographia. There is also attributed to him an anatomical work, printed in 1671, in folio.