The armillary sphere, the 2^nd issue of the «Historic Instruments series», is an early marvel of astronomical ingenuity. In its complex form, this remarkable device elegantly captures celestial and terrestrial circles. With the Earth at its center, this celestial globe is equipped with degrees for angular measurements.

During the 17^th and 18^th centuries, such splendid contraptions graced the parlours of academics, suspended in the air, perched upon ornate stands, or clutched by an elegant handle. The armillary sphere was allegedly invented separately in ancient China during the 4^th century BC and ancient Greece during the 3^rd century BC.