Christopher Columbus--how he did it

The Great enterprise

The Motives

Evidence and clues: Getting the facts

The Size of the Earth

The Distance across the Atlantic

Winds and currents

Secret evidence

The Means: Government support and financing

Reliable ships

A Competent crew

Adequate supplies

Instruments to find the way: Compass

Sand glass

Sounding lead

Quadrant

Astrolabe

Maps and charts

The Journey: Finding the way

Life at sea

The Discovery.