to a clearer demarcation of dominions in South America. In 1762 after the surrender of Colonia del Sacramento, Pedro de Cevallos went to the Portuguese, demanding the "eviction of the Yacuí River and areas of Rio Pardo, Santo Amaro, Rio Grande, San Gonzalo, San Miguel and Chuy, as well as Martín García Island and Dos Hermanas Island." In 1763, the Military Command at Maldonado was created to take care of security in the east. In 1772 Bernardo Lecocq developed the fortifications of Fuerte de San Miguel here. Eventually, however, Spain would lose influence over these territories. For the sake of demarcating the Hispano-Lusitanian boundary, both Spain and Portugal brought to the area a significant number of scientists. Work in the Guardia de Chuy began in February 1784. It is presumed that in 1826, there was a farmhouse in Chuy, as Leonardo Olivera after the famous Sableada del Chuy, on the first day of the year, he wrote that it was a surprise to Brazilians, "leaving over twenty dead behind, as I mentioned to Your Excellency, I left a captain and a wounded soldier in a house of Chuy, not knowing where to take them, so that a certain family would take care of their wounds." The 1861 map of the area by Emilio Laviña includes a ranch, stalls and a store belonging to the firm Peyre Seijo & Co. In addition to this general trade store, there existed a chemist and a teacher named Marcelino Villazuso, who gave private lessons for many years. The growing importance of this border and the existence of military posts on the Brazilian side, prompted the authorities to install a police station or Comandancia de Frontera depending on Maldonado in 1872. In 1888, the town was recognized as such by the department. The Economic Administrative Board Rocha urged neighbours to form a Neighbourhood Commission (first authorities to address local issues), and these were grouped immediately notifying the Honourable Board Rocha. Uruguay and Brazil inherited differences resulting from the ongoing litigation, which would be amended in repeated boundary treaties with the placement of boundary markers in the twentieth century. On 7 May 1913, a convention was signed to amend the limit on the San Miguel river. On 20 December 1933 a Legal Status of Border was established and on 21 July 1972 bilateral notices were exchanged about the waterfront borders at the height of the mouth