Four or five thousand horses, apparently free but whose invisible riders were concealed, according to the Indian fashion, along their flanks, were coming at a frightful pace against the barricades. Two rounds of canister produced disorder in their ranks, without checking their speed, and they fell like lightning on the defenders of Población del Sur. Then began one of those terrific fights of the Indian frontier, a cruel and indescribable contest, in which no prisoners were made, the bolas perdidas, the laquis, the bayonet, and the lance, were their sole weapons. The Indians were immediately reinforced, but the Spaniards did not give way an inch. This desperate struggle lasted for about two hours; the Patagonians seemed to give ground, and the Argentines redoubled their efforts to drive them back to their camp, when, suddenly, the cry was heard behind them—
"Treachery! Treachery!"
The major and the colonel, who were fighting in the front rank of the soldiers and volunteers, turned round; they were caught between two fires.
Pincheira, dressed in the uniform of a Chilian officer, was prancing at the head of a hundred gauchos, more or less intoxicated, who followed him, yelling—
"Pillage! Pillage!"
The two veteran officers exchanged a long, sad glance, and their determination was formed in a second.
The colonel hurled among the Indians a barrel of gunpowder, with a lighted fuse, which swept them off, as the wind sweeps the dust, and put them to flight. The Argentines, at the major's command, wheeled round and charged the gauchos, commanded by Pincheira. These bandits, with their sabres and bolas in their hands, dashed at the Argentines, who slipped into the open doors of the abandoned houses, in a narrow street, where the gauchos could not manoeuvre their horses. The Argentines, who were skilful marksmen, did not throw away a shot; they fell back on the river bank, and kept up a well-sustained fire on the gauchos, who had turned back, and on the Aucas, who had again escaladed the barricades, while the guns of the fort scattered canister and death among them.
The white men crossed the river without any risk, and their enemies installed themselves in the Población del Sur, filling the air with triumphant hurrahs.
The colonel ordered considerable works to be thrown up on the river bank, and placed in them two batteries, of six guns each whose fire crossed.
Through the treachery of the gauchos the Indians had seized Población del Sur, which, however, was not the key of the place; but this negative success entailed an enormous loss upon them. The colonists, through this, saw their communications interrupted with the estancias on the opposite bank, but luckily the farmers had come into Upper Carmen beforehand with their horses and cattle, and the boats were all moored under the batteries of the fort which protected them. The suburb captured by the assailants was, consequently, entirely empty.