has played a major role in supplying Chilean bases and performing numerous rescue missions, among them, the in 1972 and 2007. The Navy's most recognizable sailing-school ship, the , began operations in 1952. It since has made various trips around the world with selected cadet officers and NCOs on board trained in ship handling and operations, as a requirement for graduation. Prior to the Esmeralda, another sailing ship, the General Baquedano, fulfilled the same functions. In the 1950s, the Chilean Navy became involved in a series of incidents with the Argentine Navy and Argentine civilians in the disputed areas of the Beagle Channel and Cape Horn. These incidents took the form of incursions into Chilean waters by Argentine fishing ships, and provocations, such as the shelling of a Chilean lighthouse by the Argentine Navy during the Snipe incident of 1958. During the late 1970s, the Chilean Navy played an important role in defending Chilean sovereignty over the Picton, Lennox and Nueva islands that the Argentine Navy planned to seize. The birth of the modern Chilean Marine Corps of today began in 1964. Naval educational institutions were reformed in 1968, when president Eduardo Frei Montalva created the "Naval Specialities Schools System" with headquarters at the Las Salinas Naval Base in Viña del Mar. One of its schools, the Naval Seaman Training School, became the Seamen's School of the Navy "Captain Alejandro Navarrete Cisterna" in the same year as its centenary, in honor of the first naval seaman to rise through the ranks to become a naval officer. The NSSS soon became the Naval Polytechnic Academy in 1995, through a merger of all its component schools, with some of these schools staying as independent constituent academies. After the 1973 Chilean coup d'etat, together with the Army, the Air Force, and the Carabiniers, the navy, led by Admiral Jose Toribio Merino, became part of the government junta led by army commander in chief Augusto Pinochet. Upon the latter's resignation from the junta leadership in 1981, Adm. Merino became its chairman until March 1990, presiding over its sessions and those of the Legislative Commission. He was also, concurrently, the national defense minister. The training ship Esmeralda functioned as a floating prison and torture chamber for political prisoners during the 1973–1980 period of the military dictatorship. It is claimed that probably over a hundred persons were kept there at times and subjected to hideous treatment.