this werk of my labour or of myn engin. I nam but a lewd compilatour of the labour of olde Astrologiens, and have hit translated in myn English only for thy doctrine; and with this swerd shal I 45 sleen envye. I. The firste partie of this tretis shal reherse the figures and the membres of thyn Astrolabie, bi-cause that thou shalt han the grettre knowing of thyn owne instrument. II. The second partie shal teche thee werken the verrey 50 practik of the forseide conclusiouns, as ferforth and as narwe as may be shewed in so smal an instrument portatif aboute. For wel wot every astrologien that smalest fraccions ne wol nat ben shewed in so smal an instrument, as in subtil tables calculed for a cause. 55 III. The thridde partie shal contienen diverse tables of longitudes and latitudes of sterres fixe for the Astrolabie, and tables of declinacions of the sonne, and tables of longitudes of citeez and of townes; and as wel for the governance of a clokke as for to finde the altitude meridian; and many another 60 notable conclusioun, after the kalendres of the reverent clerkes, frere I. Somer and frere N. Lenne. IV. The ferthe partie shal ben a theorik to declare the moevinge of the celestial bodies with the causes. The whiche ferthe partie in special shal shewen a table of the verray 65 moeving of the mone from houre to houre, every day and in every signe, after thyn almenak; upon which table ther folwith a canon, suffisant to teche as wel the maner of the wyrking of that same conclusioun, as to knowe in oure orizonte with which degree of the zodiac that the mone ariseth in any latitude; 70 and the arising of any planete after his latitude fro the ecliptik lyne. V. The fifte partie shal ben an introductorie after the statutz of oure doctours, in which thou maist lerne a gret part of the general rewles of theorik in astrologie. In which fifte partie 75 shaltow finde tables of equacions of houses aftur the latitude of Oxenford; and tables of dignetes of planetes, and other noteful thinges, yif god wol vouche-sauf and his modur the mayde, mo than I be-hete, &c. PART I. HERE BIGINNETH THE DESCRIPCION OF THE ASTROLABIE. 1. Thyn Astrolabie hath a ring to putten on the thoumbe of thy right hand in taking the heighte of thinges. And tak keep, for from hennes-forthward, I wol clepe the heighte of any thing that is taken by thy rewle, the altitude, with-oute mo wordes. 2. This ring renneth in a maner turet, fast to the moder of thyn Astrolabie, in so rowm a space that hit desturbeth nat the instrument to hangen after his righte centre.