gold in a vault. Significantly, smallpox, which had spread from Central America—had considerably weakened the empire. Pizarro did not have a formidable force; with just 170 men, 1 cannon and only 27 horses, he often needed to talk his way out of potential confrontations that could have easily wiped out his party. Their first engagement was the battle of Puná, near present-day Guayaquil, Ecuador; Pizarro then founded the city of Piura in July 1532. Hernando de Soto was sent inland to explore the interior, and returned with an invitation to meet the Inca, Atahualpa, who had defeated his brother in the civil war and was resting at Cajamarca with his army of 80,000 troops. Pizarro met with the Inca, who had brought only a small retinue, and through interpreters demanded that he convert to Christianity. A widely disputed legend claims that Atahualpa was handed a Bible and threw it on the floor, the Spanish supposedly interpreted this action as adequate reason for war. Though some chroniclers suggest that Atahualpa simply didn't understand the notion of a book, others portray Atahualpa as being genuinely curious and inquisitive in the situation. Regardless, the Spanish attacked the Inca's retinue (see Battle of Cajamarca), capturing Atahualpa. Thereby, the victory of the comparatively small Spanish force can be attributed to the presence of Spanish horses, which were unknown to the Inca before the arrival of Pizarro, as well as to the usage of guns and cannons by the Spanish men. Furthermore, the local educational investments, which had an impact on economic growth and development, did not equal those of the Spaniards, with the numeracy level of Peruvian Inca Indios amounting to half the numeracy level of Spanish invaders. Pizarro used the capture of Atahualpa to gain gold as a ransom. Atahualpa offered the Spaniards enough gold to fill the room he was imprisoned in, and twice that amount of silver. The Incas fulfilled this ransom. Over four months, almost 8 tons of gold was collected. Pizarro was supposed to let the ruler of the Incas free once the ransom was paid, but he refused to release the Inca after that and instead had him strangled in public. During Atahualpa's imprisonment Huáscar was assassinated. The Spanish maintained that this was at Atahualpa's orders; this was one of the charges used against Atahualpa when the Spanish finally decided to put him to death, in August 1533. The