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To knowe the verrey equacioun of the degre of the sonne yf so be that it falle bitwene thyn almykanteras.

For as muche as the almykanteras in thin Astrelabie ben compowned by two and two, where as somme almykanteras in sondry astrelabies be compowned by 1 and 1, or elles by 2 and 2, it is necessarie to thy lernyng to teche the first to knowe and worke with thin oune instrument. Wherfore whan that the degre of thi sonne fallith bytwixe 2 almykanteras, or ellis yf thin almykanteras ben graven with over-gret a poynt of a compas (for bothe these thinges may causen errour as wel in knowing of the tide of the day, as of the verrey ascendent), thou must worken in this wise:

Set the degre of thy sonne upon the hyer almykanteras of bothe, and wayte wel where as thin almury touchith the bordure and set there a prikke of ynke. Sett doun agayn the degre of the sunne upon the nether almykanteras of bothe, and sett there another pricke. Remeve than thin almury in the bordure evene amiddes bothe prickes, and this wol lede justly the degre of thi sonne to sitte bitwene bothe almykanteras in his right place. Ley than thy label over the degre of thi sonne, and fynd in the bordure the verrey tyde of the day, or of the night. And as verraily shalt thou fynde upon thin est orisonte thin ascendent.