[1.] The Ring. See [figs. 1] and [2]. The Latin name is Armilla suspensoria; the Arabic name is spelt alhahuacia in MS. Camb. Univ. Ii. 3. 3, but Stöffler says it is Alanthica, Alphantia, or Abalhantica. For the meaning of 'rewle,' see § 13.
[2.] The Turet. This answers nearly to what we call an eye or a swivel. The metal plate, or loop, to which it is fastened, or in which it turns, is called in Latin Ansa or Armilla Reflexa, in Arabic Alhabos.
[3.] The Moder. In Latin, Mater or Rotula. This forms the body of the instrument, the back of which is shewn in [fig. 1], the front in [fig. 2]. The 'large hole' is the wide depression sunk in the front of it, into which the various discs are dropped. In the figure, the 'Rete' is shewn fitted into it.
[4.] See [fig. 1]; Chaucer describes the 'bak-half' of the instrument first. The centre of the 'large hole amydde' is the centre of the instrument, where a smaller hole is pierced completely through. The Southe lyne (marked Meridies in figs. 1 and 2) is also called Linea Meridiei; the North lyne is also named Linea Mediæ Noctis.
[5.] The Est lyne is marked with the word Oriens; the West lyne, with Occidens.
[6.] The rule is the same as in heraldry, the right or dexter side being towards the spectator's left.
[7.] As the 360 degrees answer to 24 hours of time, 15° answer to an hour, and 5° to twenty minutes, or a Mile-way, as it is the average time for walking a mile. So also 1° answers to 4 minutes of time. See the two outermost circles in [fig. 1], and the divisions of the 'border' in [fig. 2].
[8.] See the third and fourth circles (reckoning inwards) in [fig. 1].
[9.] See the fifth and sixth circles in [fig. 1].
[10.] See the seventh, eighth, and ninth circles in [fig. 1]. The names of the months are all Roman. The month formerly called Quinctilis was first called Julius in B.C. 44; that called Sextilis was named Augustus in B.C. 27. It is a mistake to say that Julius and Augustus made the alterations spoken of in the text; what Julius Cæsar really did, was to add 2 days to the months of January, August (Sextilis), and December, and 1 day to April, June, September, and November. February never had more than 28 days till he introduced bissextile years.