Et ab eisdem centris deducto circino ad extremas diametros describantur hemicyclia, quorum unum erit aestivum, alterum hibernum.
From them as centres, the compasses are extended to the ends of the diameters and semicircles are described, of which one will be for the summer, the other for the winter.
final_alignments\Vitruvius_Architecture_Book_9.json