'O stelliferi conditor orbis
Qui perpetuo nixus solio
_Rapidum caelum turbine uersas_,
Legemque pati sidera cogis';
Boeth. Cons. Phil. lib. i. met. 5.
'Quique _agili motu_ calet _aetheris_'; id. lib. iv. met. 1.
(See the same passages in vol. ii. pp. 16, 94).
To the original nine spheres, as above, was afterwards added a tenth or
crystalline sphere; see the description in the Complaint of Scotland, ed.
Murray (E. E. T. S.), pp. 47, 48. For the figure, see fig. 10 on Plate V.,
in my edition of Chaucer's Astrolabe (in vol. iii.).