In about year 1400, Geoffrey Chaucer - yes, the poet - wrote a step-by-step guide, A Treatise on the Astrolabe, where he described in a clear, technical prose the use of the instrument, to his 10 years old son!

A Treatise on the Astrolabe (chirurgeon.org)

 

Chaucer, as in not uncommon with writers, had quite a range of jobs and interests.  Comptroller, courtier, diplomatic envoy, forester, philosopher, astronomer.  His father was a wine merchant with a royal appointment which probably helped pave the way for his son having such an interesting life and being part of a royal court.

Hanging on a wall in my home is a planisphere, which is a modern descendant of the astrolabe.  I might look at it, as I read about Chaucer's instrument.

2 hours ago, Genady said:

In about year 1400, Geoffrey Chaucer - yes, the poet - wrote a step-by-step guide, A Treatise on the Astrolabe, where he described in a clear, technical prose the use of the instrument, to his 10 years old son!

A Treatise on the Astrolabe (chirurgeon.org)

 

How interesting. 

(And nice to know his son, like mine, was called Louis.)