from land stations and the launching of antisubmarine mines and net barrages. The Navy also manned some of the coastal defense artillery batteries. In the defense operations of the Lisbon harbor, the Navy lost the minehunter Roberto Ivens, that hit an enemy mine, sinking with the death of all its crew, and a FBA seaplane, that disappeared with its crew while patrolling off the bar of the Tagus estuary. Another port that received much attention from the Portuguese Navy, was that of São Vicente, in the Cape Verde isles. São Vicente was the interface of the telegraph submarine cables that connected America, Europe and Africa, as well being a major coaling station for the Allied warships and merchant vessels that navigated in the Atlantic. In 1914, the Navy dispatched a naval infantry force and the gunships Beira and Ibo for the islands. Later, these forces were reinforced with the gunship Bengo, with antisubmarine barrages and with coastal batteries operated by the navy. From 1916 to 1918, the Portuguese naval forces in Cape Verde were able to successfully repulse several U-boat attacks against ships anchored in the São Vicente harbor. Important efforts were also made in the defense of the harbors of Leixões, Horta, Ponta Delgada, Funchal and coast of the Algarve, with engagements occurring when Ponta Delgada and Funchal were attacked and bombarded by U-boats. The Portuguese Navy also supported the naval base and air station operated by the United States Navy in Ponta Delgada and the naval air station operated by the French Naval Aviation in São Jacinto, Aveiro. A Portuguese naval air detachment was deployed to Horta, Azores and a naval air station was built in the Culatra Island, Algarve, although never activated because the War meanwhile ended. The Portuguese Navy operated in the North Atlantic, escorting merchant vessels and protecting the maritime communication lines between the Mainland and the Portuguese Atlantic isles. In one of these missions, occurred the famous Action of 14 October 1918, between the naval trawler Augusto de Castilho, under the command of Lieutenant Carvalho Araújo, and the German U-boat cruiser . U-139 attacked the Portuguese liner SS San Miguel, that was navigating from Funchal to Ponta Delgada, with 209 passengers on board, under the escort of Augusto de Castilho. Despite being a small boat only armed with a 65 mm and a 47 mm guns, Augusto de Castilho engaged U-139 (armed with torpedoes