the entrance to the bay was guarded by an impregnable castle, called the Niebla, cut out of the solid rock, and by a battery, called Fort Piojo. On the south were the English fort, which commanded the watering-place, the fort of San Carlos, on a small peninsula, and Fort Amargos, whose fire crossed that of the Niebla. The entrance was further defended by the Chorocomayo redoubt and by the Castle of the Corral. Both these forts were masked by a dense forest, and the ground about them is so broken that their only communication by land was by a narrow path winding among the rocks and through the forest, and crossing a gulley which was commanded by the guns of both forts. Valdivia was ordinarily garrisoned by 800 troops and by as many militia, but at this time the militia were absent.
On the 18th January, 1820, the O'Higgins sailed into the bay, flying the Spanish flag. The Spaniards believed her to be the Prueba. Cochrane signalled for a pilot, who was sent off to him with a guard of honour, whom he made prisoners, and learned from them that the Potrillo was expected with money to pay the troops. He then proceeded in his gig to inspect the entrance to the river, under fire of the forts, for by this time his true character was discovered. Two days afterwards he captured the Potrillo, which had 20,000 dollars on board, but seeing that he had not men enough for an attack upon the place, he then went off for Talcahuano in search of more.
On the 22nd the O'Higgins reached Talcahuano, and was fortunate enough to find there the Intrepido and the Montezuma. Colonel Freyre, who was then in command of the fortress, eagerly entered into Cochrane's plans, and gave him 250 men under command of Major Beauchef. With this reinforcement he sailed again for Valdivia. On leaving the harbour the O'Higgins struck on a rock and commenced to make water rapidly, but the leak was patched up, Cochrane infusing his own spirit into his men, and declaring that she would float as far as Valdivia.
