The small sphere (height 185 mm) rests on a base of turned wood which supports the horizon circle by means of two intersecting semicircles. This circle is divided into four 90? quadrants, and bears the names of the winds: 'TRAMONTANTA GRECO LEVANTE SCIROCCO OSTRO GARBINO PONENTE MAESTRO'.
The meridian circle is graduated, and also divided into four quadrants of 90? each. Beneath the horizon is the inscription: 'HIERONIMUS CAMMILLI VVULPARIAE FLORENTI FE 1557'. The polar caps and the tropics have no engravings. The equator is graduated.
The zodiac band bears the names of the signs in Latin. The four armillae, or rings, are flat, of varying width, and bear the following names (from the outside towards the centre): 'DEFERENS DRAGONEM, DEFERENS AVGIEM, DEFERENS EPICICLVM, DEFERENS AVGIEM'.
Each of these is fixed to meridian circles without markings, which are pivoted to the axis.
See M. Miniati, Museo di Storia della scienza: Catalago (Florence, 1991).