July 31 (UPI) -- On this date in history: In 1498, on his third voyage to the New World, Christopher Columbus discovered the island of Trinidad. In 1556 Ignatius of Loyola, founder of the Jesuit order of Roman Catholic missionaries and educators, died in Rome. In 1792, director David Rittenhouse laid the cornerstone in Philadelphia for the U.S. Mint, the first building of the federal government. In 1964, Ranger 7, an unmanned U.S. lunar probe, took the first close-up images of the moon. In 1974,