The Capelinhos eruption represented the first time that a submarine eruption was documented from beginning to end. Its location near an inhabited island with good communications meant it could be intensively studied. The first activities during the eruption were identified by engineer Frederico Machado, the Director of the District Public Works Department, his assistant engineer João do Nascimento and surveyor António Denis, under the authorization of the Civil Governor, Freitas Pimentel. The Director of the Observatory in Angra, Lieutenant-Colonel José Agostinho overflew the area, and Bernado Almada (at the Prince Albert of Monaco Observatory, in Horta) sent several bulletins relating the increased seismic activity of the area.