AMBROSE, Saint, an island in the South Pacific Ocean, on the coast of Chili, four or five leagues due west from St Felix Island. It lies in Long. 80. 55. W. and Lat. 26. 13. S. There is a large rock four miles to the northward of the island, called from its appearance Sail-rock. Captain Roberts, who was there in 1792, found St Felix Island inaccessible. On St Ambrose Island his crew, in seven weeks, killed 13,000 seals. The island has little else to recommend it. Fish and crawfish abound.