Cosmography

Key components labeled within the diagram include:

• Movable Meridian: The outer vertical ring graduated with degrees (0 to 90 in four quadrants).
• Horizon: The horizontal ring bisecting the sphere.
• Zodiac: The wide diagonal band containing the signs of the zodiac (labeled: Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn).
• Equator: The central horizontal circle of the celestial sphere.
• Tropics: Labeled "Tropic of Cancer" and "Tropic of Capricorn."
• Polar Circles: Labeled "Arctic Pole" at the top and "Antarctic Pole" at the bottom.
• Colures: Labeled "Colure of the Equinoxes" and "Colure of the Solstices."
• Axis: The central rod passing through the poles.
• Zenith and Nadir: Labeled at the very top and bottom of the meridian ring.
• Cardinal Directions: "SOUTH" on the left and "NORTH" on the right.

The entire apparatus rests on two ornate pillars connected by a base labeled "MERIDIAN LINE."