* 1629 – Christiaan Huygens, Dutch mathematician ( d. 1695 )

In 1691 Gottfried Leibniz, Christiaan Huygens, and Johann Bernoulli derived the equation in response to a challenge by Jakob Bernoulli.

The mathematical description was derived in 1659 by Dutch physicist Christiaan Huygens.

Augustin-Jean Fresnel did more definitive studies and calculations of diffraction, made public in 1815 and 1818, and thereby gave great support to the wave theory of light that had been advanced by Christiaan Huygens and reinvigorated by Young, against Newton's particle theory.

It was notable for containing the principles of the stereographic and the orthographic projections, and it inspired the works of Desargues and Christiaan Huygens.

* Christiaan Huygens 1629 – 1695 ( Netherlands )

The Huygens – Fresnel principle ( named after Dutch physicist Christiaan Huygens and French physicist Augustin-Jean Fresnel ) is a method of analysis applied to problems of wave propagation both in the far-field limit and in near-field diffraction.

* Christiaan Huygens

Christiaan Huygens, prior to Newton, had hypothesized that light was a wave propagating through an aether, but Newton rejected this idea.

In 1668, Wilkins proposed using Christopher Wren's suggestion of a pendulum with a half-period of one second to measure a standard length that Christiaan Huygens had observed to be 38 Rhineland or English inches ( 997mm ) in length.

* 1655 – Saturn's largest moon, Titan, is discovered by Christiaan Huygens.

There has been some debate about who the original inventor of the magic lantern is, but the most widely accepted theory is that Christiaan Huygens developed the original device in the late 1650s.

This phenomenon was first observed by Christiaan Huygens in 1665.

Christiaan Huygens published the first book on probability

Christiaan Huygens ( 1657 ) gave the earliest known scientific treatment of the subject.

File: Christiaan Huygens-painting. jpeg | Christiaan Huygens ( 1629-1695 ): studied the rings of Saturn and discovered its moon Titan, invented the pendulum clock, studied optics and centrifugal force, theorized that light consists of waves ( Huygens – Fresnel principle ) which became instrumental in the understanding of wave-particle duality.

Christiaan Huygens published a book on the subject in 1657 and in the 19th century a big work was done by Laplace in what can be considered today as the classic interpretation.

From its invention in 1656 by Christiaan Huygens until the 1930s, the pendulum clock was the world's most precise timekeeper, accounting for its widespread use.

The pendulum clock was invented in 1656 by Dutch scientist Christiaan Huygens, and patented the following year.

Optics, for instance, was revolutionized by people like Robert Hooke, Christiaan Huygens, René Descartes and, once again, Isaac Newton, who developed mathematical theories of light as either waves ( Huygens ) or particles ( Newton ).

The government successfully repressed the Indian protesters, but the public outcry over the harsh treatment of peaceful Indian protesters by the South African government forced South African leader Jan Christiaan Smuts, himself a philosopher, to negotiate a compromise with Gandhi.

The old Raadsaal in Bloemfontein, with the statue of Christiaan de Wet

A week later he was buried in the Grote Kerk in the Hague, together with his son, the famous scientist Christiaan Huygens.

In 1673 Dutch scientist Christiaan Huygens in his mathematical analysis of pendulums, Horologium Oscillatorium, showed that a real pendulum had the same period as a simple pendulum with a length equal to the distance between the pivot point and a point called the center of oscillation, which is located under the pendulum's center of gravity and depends on the mass distribution along the length of the pendulum.

In 1673, while working with Christiaan Huygens and Gottfried Leibniz in Paris, he became interested in using a vacuum to generate motive power.

Along with Christiaan Cornelissen, he cited as example US trade-unions, where trade-unions composed of skilled qualified workers sometimes opposed themselves to un-skilled workers in order to defend their relatively privileged position.

He was admitted to the ICU of the Christiaan Barnard Memorial Hospital with a serious skull fracture.

In 1611, Johannes Kepler described how a telescope could be made with a convex objective lens and a convex eyepiece lens and by 1655 astronomers such as Christiaan Huygens were building powerful but unwieldy Keplerian telescopes with compound eyepieces.

In this way medical officer Christiaan Eijkman was seconded as assistant to the Pekelharing-Winkler mission, together with his colleague M. B. Romeny.

Along with the German Theodore Noldeke and the Dutch Christiaan Snouck Hurgronje, he is considered the founder of modern Islamic studies in Europe.

During the 1960s she also had an affair with heart transplant pioneer Christiaan Barnard.

Right to left: Rob Machado ( with sunglasses ), Christiaan Bailey, Kelly Slater & Sam George

This date can be very accurately established from Thevenot's correspondence with scientist Christiaan Huygens.

* Bondi Hipsters is a web series by Christiaan Van Vuuren and Nick Boshie with over 4 million views

Kelly Slater with fellow pro surfers Rob Machado and Christiaan Bailey

* Christiaan Huygens designs the first working pendulum clock, which is sufficiently accurate to be fitted with both a minute hand and a second hand.

This worked to some extent, during his studies he was a coxswain with their rowing club " Triton " and organized a national congress for science students with their science discussion club " Christiaan Huygens ".

Christiaan Huygens, in a letter dated June 8, 1694, wrote to Leibniz, " I do not know if you are acquainted with the accident which has happened to the good Mr Newton, namely, that he has had an attack of phrenitis, which lasted eighteen months, and of which they say his friends have cured him by means of remedies, and keeping him shut up.

Sir Frederick Gowland Hopkins OM FRS ( 20 June 1861 – 16 May 1947 ) was an English biochemist who was awarded the Nobel Prize in Physiology or Medicine in 1929, with Christiaan Eijkman, for the discovery of vitamins.

It was this work that led his being awarded ( together with Christiaan Eijkman ) the 1929 Nobel Prize in Physiology or Medicine.

Picard collaborated and corresponded with many scientists, including Isaac Newton, Christiaan Huygens, Ole Rømer, Rasmus Bartholin, Johann Hudde, and even his main competitor, Giovanni Cassini, although Cassini was often less than willing to return the gesture.