The day was exquisitely beautiful, and the sky was clear and serene. San Martin opened with a strong artillery fire from both his right and left flank. He then ordered a general advance. The horse grenadiers, who had accompanied him from Argentina, charged the Spanish lines furiously. Other battalions charged the royalist right, which was made up of veterans of the Peninsular wars. The Spanish cavalry were driven from the field. San Martin brought his reserves into action and the Spaniards began an orderly retreat. They withdrew to the buildings and walled enclosures of a _hacienda_. These were soon broken down by the patriot guns. The closing scenes were horrible. The infuriated patriots showed no mercy, and the _patios_ and gardens were soon littered with the dead. The result, after several hours of fierce fighting, was of a most decisive character. The Spaniards’ loss was nearly three thousand. The remainder were flying in every direction, with the enemy in close pursuit. Osorio finally reached Talcahuano with only ten men, the remnant of the original force of five thousand that entered the battle of Maipo. The revolutionists’ loss was eight hundred killed and one thousand wounded. Spain at last realized the strength of her opposition. The war for liberty now turns toward Peru. Soon after the decisive battle of Maipo San Martin reverted to his original plan to invade Peru. The _junta_ at Buenos Aires commanded him to return to Argentina and aid them in that city. But he refused to be drawn into the local struggle between the different factions that were seeking to obtain control of the government. He began work on his new expedition with the same careful and methodical plans to gather about him an effective army as he had at Mendoza. The survivors of that army were loyal to their commander, and they willingly volunteered for this new enterprise. Others were added, and all were carefully drilled. Supplies and ammunition were gathered. It was not until 1820, however, that San Martin was ready to embark for Peru with an army of four thousand one hundred men. This force was conveyed to the Peruvian coast by the Chilean navy under command of Lord Cochrane, who played an important part in driving the Spaniards from this coast and liberating Chile and Peru from their domination.