Armillary spheres were used as astronomical instruments to determine the movements of stars around the earth. The inner sphere represents the earth and is surrounded by outer rings representing the zodiac, degrees of movement, and specific locations in the world. Our antique reproduction armillary is the perfect small size for your desk or office. - 5-1/2" tall, 3-1/4" base, 3-1/2" diameter at widest band - Antiqued brass and elegant rosewood for a beautiful vintage look. - Green felt lined base to prevent surface scratches.