The armillary sphere, number 2 in the "Historical Instruments Series," is one of the earliest marvels of astronomical ingenuity. In its complex form, this remarkable device elegantly captures the celestial and terrestrial circles. With the Earth at its center, this celestial globe is equipped with degrees for angular measurements.

In the 17th and 18th centuries, such splendid devices adorned the salons of scholars, suspended in the air, perched on ornate stands, or gripped by an elegant handle. The armillary sphere is said to have been invented separately in ancient China in the 4th century BC and in ancient Greece in the 3rd century BC.