This was because of its many marginal scales, its set of engraved plates for different latitudes and horizons, and its ornamental 'rete' or pierced metalwork which carried the fixed stars and the celestial circles.
Kungenxa yesikali esasingaphezulu, sepleyiti ezikroliweyo ezifanayo kububanzi nokuthi tyaba ngkwahlukeneyo nakwimifanekiso ethe tyaba okanye iqhekeza lesinyithi elithwele inkwenkwezi efakelweyo nesangqa esibhaka-bhakeni.