Shen Kuo completes Dream Pool Essays

1088

The Song polymath, retired from government service, compiled his Brush Talks from Dream Brook, an encyclopedic miscellany describing the magnetic compass, movable-type printing, astronomical phenomena, music, mathematics, and archaeology. It was the most wide-ranging scientific work of the medieval world, written by a single curious mind. His observation that the compass needle points slightly east of true north was the first recorded description of magnetic declination.