At a time when Europe was still struggling to throw off the Dark Ages, Shen Kuo, a Chinese scientist of the Song dynasty, made remarkable progress in an amazing variety of fields of endeavour. His Dream Pool Essays (named for Shen's garden estate), written around 1088 A.D., covered various aspects of astronomy, mathematics, physics, geology, cartography, meteorology, navigation, zoology and botany. Besides his scholarly activities, Shen Kuo was a military tactician, a statesman, an administrator and a poet; he was the ultimate Renaissance man, despite living long before the Renaissance and on the wrong continent.
The Dream Pool Essays contained the first mention of the magnetic compass. Shen recognized that magnetic north was not true north and correctly figured out the declination. He also realized that the polar star was actually a circumpolar star and through careful observation with an instrument of his own invention, he charted its rotation. These were not idle observations but were incorporated into Chinese navigation practices.
Shen Kuo and his colleague Wei Pu made accurate astronomical observations of the moon and planets by observing them three times a night over the course of five years, a project not matched until Tycho Brahe's extensive observations, 500 years later.
Dream Pool Essays contains a description of moveable type, invented by an artisan named Bi-Sheng during the reign of Emperor Renzong (1022-1063), four hundred years before Gutenberg.
After visiting Mount Yadang, Shen formulated a theory of erosion caused by moving water.
Observing sea shells embedded in a cliff, he immediately realized its significance. "This was once a seashore, although the sea is now hundreds of miles east. What we call our continent is an inundation of silt..." From the discovery of petrified bamboo in a dry northern province of China, Shen inferred a shift in climate, probably the first published reference to climate change.
Shen was also an early ecologist who worried about the decline in tree populations due to the needs of industry. He suggested the replacement of petroleum for the pine soot used in ink production. He described the biological control of agricultural pests by predator insects.
Dream Pool Essays also contains probably the first ever mention of an unidentified flying object, a mysterious entity that apparently made regular appearances in the sky over Fanliang in Yangzhou province. It was observed to open its door to emit a great light. "The spectacle was like the rising Sun, lighting up the distant sky and woods in red." The object was nicknamed "the Pearl" by a local poet and the Pearl Pavilion was built as a viewing platform for tourists.