Cortés exchanges gifts with the Aztec Emperor, Montezuma. An excellent diplomatic move on both sides!

Tension is building between the Aztecs and the Spaniards, not to mention within Cortés's own ranks. Despite this, the conquistador rallies his troops to conquer Mexico.

Cortés sets out to conquer Mexico with his four hundred men, sixteen horses, and seven cannons. He is joined later by native forces, the Totonac warriors.

The Maestro explains how the revolutionary ideas of the early discoverers, which we now take for granted, were not always well received. Before Galileo, for example, everyone believed that the sun and all the other planets revolved around the earth!

In this video, a young Galileo gets one of his first revolutionary ideas on how to measure time. Pretty impressive for a fourteen-year-old, huh?

Episode nine of this series focuses on Galileo, a prolific inventor and scientist. He discovered the principle of the simple pendulum motion, very useful in the measure of time and later in the making of clocks.

In part four of this episode on "The Discoverers," Galileo, now a reputable scholar at the University of Padua, proceeds to make a telescope out of lenses with the help of his instrument maker, Marc'Antonio. In this cartoon, an attempt is made to explain Galileo's discoveries.

In part five of this episode on "The Discoverers," Galileo is warned. His belief that the Earth revolves around the sun is sacrilegious. Giordano Bruno, who claimed this fact, was burned as a heretic by the Inquisition Tribunal.

Galileo is about to throw caution to the wind and reveal his startling discoveries about planet Earth.