ACUNA, CHRISTOVAL DE (1597—c. 1676), Spanish Jesuit missionary and explorer, was born at Burgos in 1597. He was sent on mission work to Chile and Peru, where he became rector of the college of Cuenca. In 1639 he accompanied Pedro Texiera in his second exploration of the Amazon, in order to take scientific observations, and draw up a report for the Spanish Government. The journey lasted ten months; on the explorer's arrival in Peru, Aculia prepared his narrative, while awaiting a ship for Europe. The king of Spain, Philip IV., received the author coldly, and it is said even tried to suppress his book, f ear ing that the Portuguese, who had just revolted from Spain (1640), would profit by its information. Eventually Aculia re turned to South America, where he died, probably soon after 1675. His Nuevo Descubrimiento del Gran Rio de las Amazonas was published at Madrid in 1641 ; French and English transla tions (the latter from the French), appeared in 1682 and 1698. ACUPRESSURE, the name given to a method of restraining haemorrhage, introduced by Sir J. Y. Simpson, the direct pressure of a metallic needle, either alone or assisted by a loop of wire, being used to close the vessel near the bleeding point.