Zhang Sixun - Life and Works

Life and Works

Zhang Sixun, although innovative, built upon the efforts of those before him. It was the Han Dynasty era scientist and engineer Zhang Heng (78-139 AD) who invented the first hydraulic-powered (i.e. with waterwheel and clepsydra) armillary sphere. In addition, it was the Tang Dynasty era Buddhist monk and engineer Yi Xing (683-727 AD) who invented the first hydraulic-powered armillary sphere that incorporated the escapement mechanism. Yet Zhang Sixun applied some innovative ideas of his own in order for his hydraulic-powered armillary sphere to function. His astronomical armillary sphere and clock was much like that of the later statesman Su Song (1020-1101 AD), incorporating the scoop-bearing driving-wheel and gearing, together with 19 clock jacks to report and sound the hours. His device also employed the use of liquid mercury in the closed circuit of the clepsydra and waterwheel instead of water, because water would freeze easily during winter, while mercury could assure smooth and continual function and time-keeping during the cold season. Later Ming Dynasty clocks had the same concern in mind when they employed the use of falling sand grains to push the wheel drive. The later Su Song wrote that after Zhang's death, no one could replicate what he had achieved, much like with Su Song himself and his astronomical clock tower after his own death.

Read more about this topic:  Zhang Sixun

Famous quotes containing the words life and, life and/or works:

    The principal thing children are taught by hearing these lullabies is respect. They are taught to respect certain things in life and certain people. By giving respect, they hope to gain self-respect and through self-respect, they gain the respect of others. Self-respect is one of the qualities my people stress and try to nurture, and one of the controls an Indian has as he grows up. Once you lose your self-respect, you just go down.
    Henry Old Coyote (20th century)

    ... it is an uneasy lot at best, to be what we call highly taught and yet not to enjoy: to be present at this great spectacle of life and never to be liberated from a small hungry shivering self—never to be fully possessed by the glory we behold, never to have our consciousness rapturously transformed into the vividness of a thought, the ardour of a passion, the energy of an action, but always to be scholarly and uninspired, ambitious and timid, scrupulous and dim-sighted.
    George Eliot [Mary Ann (or Marian)

    That man’s best works should be such bungling imitations of Nature’s infinite perfection, matters not much; but that he should make himself an imitation, this is the fact which Nature moans over, and deprecates beseechingly. Be spontaneous, be truthful, be free, and thus be individuals! is the song she sings through warbling birds, and whispering pines, and roaring waves, and screeching winds.
    Lydia M. Child (1802–1880)