Caption: Geoffrey Chaucer (c. 1343--1400) with an astrolabe.

Chaucer was an amateur adept at Medieval European astronomy and wrote A Treatise on the Astrolabe (1391) addressed to his son, but probably intended for us all:

Litell Lowis my sone, I have perceived wel by certeyne evidences thyn abilite to lerne sciences touchinge noumbres and proporciouns; and as wel considere I thy bisy preyere in special to lerne the Tretis of the Astrolabe. Than, for as mechel as a philosofre seith, "he wrappeth him in his frend, that condescendeth to the rightful preyers of his frend", ther-for have I geven thee a suffisaunt Astrolabe as for oure orizonte, compowned after the latitude of Oxenford; up-on which, by mediacion of this litel tretis, I purpose to teche thee a certein nombre of conclusions apertening to the same instrument.
Geoffrey Chaucer (c. 1343--1400), opening of the A Treatise on the Astrolabe (1391). Quotation from A Treatise on the Astrolabe: test presented in Middle English and Modern English side-by-side.

Credit/Permission: © David Jeffery, 2003 / Own work.
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