Pierre-Simon Laplace

John Michell first proposes the idea that there are such things as black holes, which he calls "dark stars", in a paper for the Philosophical Transactions of the Royal Society of London, read on November 27, 1783.

Having accepted Newton’s corpuscular theory of light, which posits that light consists of minuscule particles, he reasons that such particles, when emanated by a star, would be slowed down by its gravitational pull, and thought that it might therefore be possible to determine the star's mass based on the reduction in speed.

This insight led in turn to the recognition that a star's gravitational pull might be so strong that the escape velocity would exceed the speed of light.

Michell has calculated that this would be the case with a star more than  five hundred times the size of the Sun.

Since light would not be able to escape such a star, it would be invisible.

 In his own words:

    If there should really exist in nature any bodies, whose density is not less than that of the sun, and whose diameters are more than 500 times the diameter of the sun, since their light could not arrive at us; or if there should exist any other bodies of a somewhat smaller size, which are not naturally luminous; of the existence of bodies under either of these circumstances, we could have no information from sight; yet, if any other luminous bodies should happen to revolve about them we might still perhaps from the motions of these revolving bodies infer the existence of the central ones with some degree of probability, as this might afford a clue to some of the apparent irregularities of the revolving bodies, which would not be easily explicable on any other hypothesis; but as the consequences of such a supposition are very obvious, and the consideration of them somewhat beside my present purpose, I shall not prosecute them any further.
     ("On the Means of Discovering the Distance, Magnitude, &c. of the Fixed Stars, in Consequence of the Diminution of the Velocity of Their Light, in Case Such a Diminution Should be Found to Take Place in any of Them, and Such Other Data Should be Procured from Observations, as Would be Farther Necessary for That Purpose. By the Rev. John Michell, B. D. F. R. S.” In a Letter to Henry Cavendish, Esq. F. R. S. and A. S." (PDF), Philosophical Transactions of the Royal Society of London 74 :35-57)

Michell suggests that there might be many "dark stars" in the universe, and today astronomers believe that black holes do indeed exist at the centers of most galaxies.

Similarly, Michell proposes that astronomers can detect "dark stars" by looking for star systems that behave gravitationally like two stars, but where only one star can be seen.

Michell argues that this will show the presence of a "dark star".

It is an extraordinarily accurate prediction.

All of the dozen candidate stellar black holes in our galaxy (the Milky Way) are in X-ray compact binary systems.

A dozen years after Michell comes up with the concept of black holes, the French mathematician Pierre-Simon Laplace will suggest essentially the same idea in his 1796 book, Exposition du Système du Monde.

Napoleon Bonaparte was born on August 15, 1769, the second of eight children, in his family's ancestral home Casa Buonaparte, located in the town of Ajaccio, Corsica, a year after the island was transferred to France by the Republic of Genoa.

He was christened Napoleone di Buonaparte, probably acquiring his first name from an uncle (though an older brother, who did not survive infancy, was also named Napoleone).

He is called by this name until his twenties, when he adopts the more French-sounding Napoléon Bonaparte.

The Corsican Buonapartes originate from minor Italian nobility of Lombard origin, who had come to Corsica from Liguria in the sixteenth century.

2012 DNA tests found some of the family's ancestors were from the Caucasus region. (lefigaro.fr (15 January 2012). "Le Figaro – Mon Figaro : Selon son ADN,les ancêtres de Napoléon seraient du Caucase!".

Le Figaro.

Retrieved 28 June 2012.)

The study found haplogroup type E1b1c1* originating in Northern Africa circa 1200 BCE.

("Haplogroup of the Y Chromosome of Napoléon the First; Gerard Lucotte, Thierry Thomasset, Peter Hrechdakian; Journal of Molecular Biology Research".

December 2011.

Retrieved 28 June 2012.)

Naploeon’s father Nobile Carlo Buonaparte, an attorney, had been named Corsica's representative to the court of Louis XVI in 1777.

The dominant influence of Napoleon's childhood was his mother, Letizia Ramolino, whose firm discipline restrained a rambunctious child.

Napoleon has an elder brother, Joseph; and younger siblings Lucien, Elisa, Louis, Pauline, Caroline and Jérôme.

There were also two other children, a boy and girl, who were born before Joseph but died in infancy.

Napoleon was baptized as a Catholic just before his second birthday, on 21 July 1771 at Ajaccio Cathedral.

Napoleon's noble, moderately affluent background and family connections had afforded him greater opportunities to study than were available to a typical Corsican of the time.

In January 1779, Napoleon had enrolled at a religious school in Autun, mainland France, to learn French, and in May he was admitted to a military academy at Brienne-le-Château.

He speaks with a marked Corsican accent and will never learn to spell properly.

Teased by other students for his accent, Napoleon had applied himself to reading.

An examiner observed that Napoleon "has always been distinguished for his application in mathematics.

He is fairly well acquainted with history and geography...This boy would make an excellent sailor."

(McLynn, Frank (1998).

Napoleon, p.21.

Pimlico) On completion of his studies at Brienne in 1784, Napoleon had been admitted to the elite École Militaire in Paris; this had ended his naval ambition, which had led him to consider an application to the British Royal Navy.

Instead, he had trained to become an artillery officer and when his father's death reduced his income, had been forced to complete the two-year course in one year.

He is the first Corsican to graduate from the Ecole Militaire and is examined by the famed scientist Pierre-Simon Laplace, whom Napoleon will later appoint to the Senate.

Upon graduating in September 1785, Bonaparte is commissioned a second lieutenant in La Fère artillery regiment, initially serving served on garrison duty in Valence, Drôme.

Each state in pre-revolutionary Europe has its own system of units of measure.

Some countries, such as Spain and Russia, see the advantages of harmonizing their units of measure with those of their trading partners.

However, vested interests who profit from variations in units of measure oppose this.

This is particularly prevalent in France, where the huge inconsistency in the size of units of measure was one of the causes that, in 1789, led to the outbreak of the French Revolution.

During the early years of the revolution, savants including the Marquis de Condorcet, Pierre-Simon Laplace, Adrien-Marie Legendre, Antoine Lavoisier and Jean-Charles de Borda set up a Commission of Weights and Measures.

The commission is of the opinion that the country should adopt a completely new system of measure based on the principles of logic and natural phenomena.

Logic dictates that such a system should be based on the radix used for counting.

Their report of March 1791 to the Assemblée nationale constituante considers but rejects the view of Laplace that a duodecimal system of counting should replace the existing decimal system; the view that such a system is bound to fail prevails.

The commission's final recommendation is that the assembly should promote a decimal-based system of measurement.

The leaders of the assembly accept the views of the commission.

Initially France attempts to work with other countries towards the adoption of a common set of units of measure.

Among the supporters of such an international system of units is Thomas Jefferson who, in 1790, had presented to Congress a document titles Plan for Establishing Uniformity in the Coinage, Weights, and Measures of the United States, in which he advocated a decimal system that used traditional names for units (such as ten inches per foot).

The report had been considered but not adopted by Congress.

Franz Xavier von Zach publishes Tables of the Sun (Gotha, 1792; new and improved edition, Gotha, 1804), and numerous papers on geographical subjects, particularly on the geographical positions of many towns and places, which he determines on his travels with a sextant.

Zach had studied physics at the Royal University of Pest, served for some time in the Austrian army, and taught at the University of Lemberg (now Lviv, Ukraine).

He lived in Paris in 1780–83, and in London from 1783 to 1786 as tutor in the house of the Saxon ambassador, Hans Moritz von Brühl.

In Paris and London he had entered the circles of astronomers like Joseph de Lalande, Pierre-Simon Laplace and William Herschel.

In 1786 he had been appointed by Ernest II, Duke of Saxe-Gotha-Altenburg, as director of the new observatory on Seeberg hill at Gotha, completed in 1791.

The world's first geographical society, the Société de géographie, is established on December 15, 1821, in the Paris Hôtel de Ville.

Among its two hundred and seventeen founders are some of the greatest scientific names of the time, including Pierre-Simon Laplace (the Society's first president), Georges Cuvier, Charles Pierre Chapsal, Vivant Denon, Joseph Fourier, Gay-Lussac, Claude Louis Berthollet, Alexander von Humboldt, Jean-François Champollion, and François-René de Chateaubriand.

Most of the men of science who had accompanied Bonaparte in his Egyptian expedition are members: Edme-François Jomard, Conrad Malte-Brun, Jules Dumont d'Urville, Jules Paul Benjamin Delessert, Hottinguer, Henri Didot, Bottin and others such as Jean-Baptiste Benoît Eyriès.