word for the islands as "mexéelam." The Kumeyaay called the islands mat hasil ewik kakap. Later archeological expeditions have corroborated reports of ceramic artifacts on the islands, with ceramic fragments found on South Island. These ceramic fragments appear to have been fired in an open oven, and were likely used as cooking pots. Analysis of the artifacts suggests their production techniques are consistent with those of Yuman ceramic manufacture. Radiocarbon dating of abalone shells within the vicinity of the ceramic artifacts suggest that site was occupied intermittently from at least 1390 to 820 calibrated years BP. In 1542, Spanish explorer Juan Rodríguez Cabrillo was the first European to notice the islands, describing them as Las Islas Desiertas (the desert islands) due to their barren lack of soil. In 1602 the priest for Sebastián Vizcaíno's expedition, Father Antonio de la Ascención, called them (the four crowned ones) to honor the four brothers who died for their Christian faith. They are also known by a number of other names, with later fisherman, upon seeing floating coffins, ghostly faces and shrouded bodies amid the rocks dubbing them Old Stone Face, The Sarcophagi, Dead Man's Island, and Corpus Christi. They have also been referred to as the Sentinels of San Diego Bay. Commercial ventures Starting in the 1860s, advertisements for day trips to the islands began making appearances in local newspapers. At the same time, commercial fishing ventures also started, focusing mostly on rock cod. In 1872, the Mexican Navy began visiting the islands to prevent trespassing and reduce the damage from human impact, although business ventures still proceeded regardless. That same year, building stone of high quality was discovered on North Island. Colonel Manuel Ferrer and Tore Fidel Pujal, the editor of the newspaper La Baja California, secured the North Island in 1873, planning to use the stone. The last newspaper report of this venture was in 1882. At one point, the islands were used as a way station in the smuggling of Chinese immigrants into California. This ended after a group of Chinese were found starving and abandoned on the island. In the 1920s and 1930s, during prohibition, the cove on the northeast side of South Coronado Island was used as a meeting place for alcohol smugglers. Since it was the time before radar, and as foggy nights are common on the islands, the large number of boats frequently resulted in collisions.