sentences:  After the visit to Rome in 1636 of the English physician George Ent (later a fellow of the Royal Society), a correspondence ensued.Cassiano sent Ent specimens of petrified wood and a tabletop made from fossil wood, which had come from the estates of Federico Cesi at Acquasparta; the specimens and the tabletop were shown to early meetings of the Royal Society and had a significant part in the developing debate on the origin of fossils.The correspondence also records exchanges of books between London and Rome; among medical matters there is news of William Harvey and his works.