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To knowe the verrey degre of eny maner sterre, straunge or unstraunge, after his longitude; though he be indetermynat in thin Astralabye, sothly to the trouthe thus he shal be knowe.

Tak the altitude of this sterre whan he is on the est syde of the lyne meridionall, as nye as thou mayst gesse; and tak an ascendent anon right by som manere sterre fix which that thou knowist; and forget not the altitude of the firste sterre ne thyn ascendent. And whan that this is don, aspye diligently whan this same firste sterre passith eny thyng the south westward; and cacche him anon right in the same nomhre of altitude on the west syde of this lyne meridional, as he was kaught on the est syde; and tak a newe ascendent anon-ryght by som maner sterre fix which that thou knowist, and forget not this secunde ascendent. And whan that this is don, rekne than how many degrees ben bitwixe the firste ascendent and the secunde ascendent; and rekne wel the myddel degre bitwene bothe ascendentes, and set thilke myddel degre upon thyn est orizonte; and wayte than what degre that sitte upon the lyne meridional, and tak there the verrey degre of the ecliptik in which the sterre stondith for the tyme. For in the ecliptik is the longitude of a celestiall body rekned evene fro the heved of Aries unto the ende of Pisces; and his latitude is rekned after the quantite of his declynacioun north or south toward the polys of this world.

As thus: Yif it be of the sonne or of eny fix sterre, rekne hys latitude or his declinacioun fro the equinoxiall cercle; and if it be of a planete, rekne than the quantite of his latitude fro the ecliptik lyne, all be it so that fro the equinoxiall may the declinacioun or the latitude of eny body celestiall he rekned after the site north or south and after the quantite of his declinacioun. And right so may the latitude or the declinacioun of eny body celestiall, saaf oonly of the sonne, after hys site north or south and after the quantite of his declinacioun, be rekned fro the ecliptik lyne; fro which lyne alle planetes som tyme declinen north or south saaf oonly the forseide sonne.