Mathematician, physicist and astronomer (1629 - 1695)
Many important discoveries and inventions are due to Christiaan Huygens. In
1655, using a telescope he had improvised with lenses of his own manufacture,
he discovered Saturn's first moon, Titan, and also that Saturn had a ring round
Huygens is also the inventor of the pendulum clock. In 1673 he published his book Horologium Oscillatorium in which he discusses this clock and the theory on which it was based.