The squadron of Peru, had not been renovated in the last eleven years, and almost all ships were immobilized and repair process. However, the monitor "Huascar" was constituted a serious threat to maritime communication lines that supported the war effort in Chile. On May 26, 1879 Antofagasta attacked the next day captured two merchant ships in Cobija, on June 3 is seen by the ironclad "Blanco" and the gunboat "Magallanes", but manages to escape after a short artillery duel during the night of July 10 Iquique penetrate and attack naval units blocking the port, sailed July 17 to intercept a convoy of Chile, a week after capturing the carriage "Rimac", with 300 police and war supplies. Although it was the priority for the Chilean navy, always managed to sneak, using simplicity as a strategy. He attacked when he had retired and when the situation required it, this principle allowed him to have the Chilean navy at bay for long. Masa: You focus the effects of combat power in place and time, to achieve positive results. The principle of mass, was put into practice during the conflict in 1981, when the proper equipment of Ecuadorian soldiers, indicated its intention to establish a strong resistance to this was added, the harsh features of the area, with dense forests and mountain range, these factors facilitated the infiltration of Ecuador, whose posts were operating between 200 and 400 soldiers. On January 28, 1981, with Ecuador's refusal to withdraw its troops from the territory of Peru, it was decided to carry out the eviction operation. .