In 1816 Abascal thought that his work was virtually completed and that he had earned the right to retire. Resistance was confined to Buenos Aires, to the thinly populated provinces of Tucuman and Cuyo, and to the banks of the Orinoco. The Argentine revolutionists were fighting among themselves, and that they must succumb before an advance in force from the Bolivian plateau appeared certain. The last act of his administration was to send out a fleet that compelled four Argentine ships which Admiral William Brown had brought around the Horn to withdraw to the Atlantic. He was succeeded by General Pezuela, a strategist of no mean abilities, who had borne a brilliant part in the Bolivian campaigns. The new viceroy straightway set about final preparations for a decisive advance across the pampas to Buenos Aires, but like a thunderbolt from a clear sky came the news that San Martin had made a sudden descent on Chile and won the battle of Chacabuco, annihilating the Spanish forces in that country. Pezuela saw himself obliged to begin a war to reduce Chile to obedience--an undertaking sure to be long and arduous, and in which he must encounter a general whose technical mastery of the profession had enabled him to create an army equal in discipline and effectiveness to any the viceroy might hope to throw against him. Pezuela abandoned the idea of an immediate Argentine campaign, and contented himself with maintaining a defensive attitude on the Bolivian frontier. He managed to repulse the armies which the Buenos Aireans sent against Bolivia, but it was in vain that he poured into Chile all the troops he could possibly spare. They were overthrown and annihilated in the decisive battle of Maipo. The viceroy sent for help to Spain and New Granada, but Venezuela had risen in insurrection under Bolivar and Paez; and it was impossible to spare any considerable number of troops from the Caribbean.