Shen Kua Essay, Research Paper

Astronomer, Shen Kua was born in China in the year 1026. His family had an

unbroken tradition of being civil servants. Thus his father was a local

administrator of many posts from Szechwan in the west to the international port

of Amoy. At Sixteen years old Shen Kua left his home to travel with his father

from post to post. While traveling with his father, Shen Kua learned the

responsibilities of a local administrator. These responsibilities include a

broad range of technical and managerial problems in public works, finance,

improvement of agriculture, and maintenance of waterways. In 1051 his father

died and after a two year mourning period Shen Kua received his first

appointment as a local administrator at the age of twenty two. Soon after his

appointment he showed his skill in ability to plan by designing and overseeing a

drainage and embankment system that reclaimed some hundred thousand acres of

swampland for agriculture. A few years later he passed the national examinations

and was assigned a post in Yangchow. While in Yangchow he impressed the Governor

Chang Ch’u so much that he recommended that Shen be appointed to the department

of Financial Administration. It was about this time that he began to study

astronomy. His first works as an astronomer came when he set down clear

explanations concerning the sphericity of the sun and the moon as proved by

lunar phases, of eclipse limits and the retrogradation of the lunar nodes. These

explanations gave the ability to visualize motions in space Which in the past

was only best implicit in numerical procedures of traditional astronomy and

seldomly discussed in technical writing. Because of this work Shen was given an

additional appointed as director of the Astronomical Bureau. His first project

as director was a major calendar reform. This reform started with a series of

daily observations of the stars that lasted over five years. While these

observations where being performed Shen realized the need for a major redesign

of major astronomical instruments. The most significant change that Shen made

was to the gnomon. The gnomon was still being used to measure the noon shadow

and fix the solstices. Shen redesigned the armillary sphere that is used to make

angular measurements, and the clepsydra which determines the time that

observations are made. He improved the armillary sphere by improving the

diameter of the naked eye sighting tube. Shen noticed that the polestar could no

longer be seen in the sighting tube at night. He slowly widened the tube by

using the plots of the polestar three times a night for three months to adjust

the aim. His new calibration revealed that the tube was slightly three degrees

off. The clepsydra also had calibration problems as well, in the past day and

night were separately divided by hours. Shen realized that day and night hours

were different from season to season. The time was read from float rods in an

overflow-tank. Shen saw these problems and proposed a new design for these float

tanks. Shen also made his mark in his discussions of solar, lunar, and eclipse

phenomena. This by far was the most extraordinary of his cosmological hypothesis

that accounts for variations in planetary motions that include retrogradation.

Shen noted that the greatest planetary anamoloy happened near stationary points.

He proposed a model that suggested that the planet moved in the shape of a

willow leaf attached to one side of a periphery circle. The way the planets

changed thier direction of motion in respect to the stars was explained by the

travel from one point of the leaf to the other. This served the same purpose as

the epicycle served in Europe Shen’s writings were in part considered to be the

highest achievement in traditional Chinese mathematical astronomy. After his

impeachment from office at the age of fifty-one Shen moved to a small piece of

land in the country. It was there that Shen completed three books and an atlas

of China. One of these books was called "Brush Talks From The Dream

Brook". This book includes some of Shen Kua’s most elaborate ideas on such

things as regularities underlying the phenomenal, technical skills,

deliberations of materia medica, and many miscellaneous notes.