Monday, July 21, 2014

Jean Picard and his Love for Accuracy

Jean-Félix Picard
(1620 – 1682)
On July 21, 1620, French astronomer, cartographer and hydraulic engineer Jean-Félix Picard was born. He is regarded as the founder of modern astronomy in France. He introduced new methods, improved the old instruments, and added new devices, such as Huygens' pendulum clock to record times and time intervals.

Jean-Félix Picard was born as a son of a bookseller and was allowed to study at the Jesuit Collège Royal Henry-Le-Grand, which was considered one of the best educational centers in France. It is assumed that he left the institution without a degree and moved to Paris due to the unstable situation in France. In Paris, he met the well established astronomer and mathematician Pierre Gassendi. He motivated Picard to study astronomy and Picard was allowed to assist with observations of solar and lunar eclipses. Picard became a professor of astronomy, as it is assumed, in 1655. He continued his career at the College de France in Paris, but unfortunately, there is no published work by Picard known from this period.

However, it is known that he exchanged letters with Christian Huygens, Ole Rømer, and Giovanni Cassini and it is assumed that he was highly respected as a scientist at that time. Also, he became one of the first members of the Academie Royal des Sciences one year after its founding in 1666. Between 1669 and 1670, Picard was the first person to measure the size of the Earth to a reasonable degree of accuracy, building on Maurolycus's methodology and Snellius's mathematical discoveries. Picard was honored with a pyramid at Juvisy-sur-Orge for his significant scientific effort. He was able to achieve this by measuring one degree of latitude along the Paris Meridian using triangulation along thirteen triangles stretching from Paris to the clock tower of Sourdon, near Amiens. His measurements produced a result of 110.46 km for one degree of latitude, which gives a corresponding terrestrial radius of 6328.9 km. The polar radius has now been measured at just over 6357 km. This was an error only 0.44% less than the modern value. This was another example of advances in astronomy and its tools making possible advances in cartography. Picard was the first to attach a telescope with crosswires to a quadrant, and one of the first to use a micrometer screw on his instruments. The quadrant he used to determine the size of the Earth had a radius of 38 inches and was graduated to quarter-minutes. The sextant he used to find the meridian had a radius of six feet, and was equipped with a micrometer to enable minute adjustments. These equipment improvements made the margin of error only ten seconds, as opposed to Tycho Brahe's four minutes of error. This made his measurements 24 times as accurate. It is believed that Isaac Newton used this value in his theory of universal gravitation. Picard's method and measurements were the topic of his Mesure de la terre, published in 1671.

He was also an important member of the team that began to compile a map of France based on scientific principles and he became a major figure in the development of scientific cartography. In 1673 he was at the Paris observatory collaborating with Cassini, Rømer, and La Hire on the institute's regular project of observations. Picard directed his attention to other projects of the Académie such as the surveying operations at Marly and Versailles. For example he became active in the problem of supplying Versailles with water. He also performed barometric experiments and became generally more and more active in the field of physics. Picard published scientific papers on hydraulics and optics. He made several suggestions to improve the telescope and left behind manuscripts on dioptrics.

At yovisto, you may be interested in a video on the CNES mission, named after the French scientist Jean-Félix Picard. CNES's Picard microsatellite is designed to simultaneously measure parameters such as the Sun's speed of rotation, radiated power, sunspots, figure and diameter, in order to better understand its inner workings.

References and Further Reading:
Related Articles in the Blog:

If you like the daily blog posts of yovisto about the history of science, please support us by clicking on the amazon links and making your next amazon purchase via our offered links. Nevertheless, please do also support your local (real world) bookstore at the corner of the street.

Sunday, July 20, 2014

Sir John Reith and the BBC

On July 20, 1889, John Charles Walsham Reith, 1st Baron Reith, was born. Sir John Reith was the first General-Director of the British Broadcasting Corporation and regarded as one of BBCs founding fathers. His concept of broadcasting as a way of educating the masses marked for a long time the BBC and similar organizations around the world.

John Reith was the founder of the BBC. He was its first general manager when it was set up as the British Broadcasting Company in 1922; and he was its first director general when it became a public corporation in 1927. He created both the templates for public service broadcasting in Britain; and for the arms-length public corporations that were to follow, especially after World War Two. Reith fought off the politicians' attempts to influence the BBC, while offering the British people programmes to educate, inform and entertain.

John Charles Walsham Reith was born on July 20th 1889 at Stonehaven, Kincardineshire, UK, as the youngest, by ten years, of seven children. His family were holidaying there from Glasgow, where his father George was a minister in the Free Church of Scotland. Reith was educated at The Glasgow Academy then at Gresham's School, Holt, Norfolk. His father refused to support any further education and apprenticed him as an engineer at the North British Locomotive Company. Serving in World War I, Reith was struck in the cheek by a bullet in October 1915, at which time he was a Lieutenant, and transferred to the Royal Engineers, where he resigned his Territorial Army commission in 1921 in the rank of a captain.

Reith had no broadcasting experience when he replied to an advertisement in The Morning Post for a General Manager for an as-yet unformed British Broadcasting Company in 1922. He later admitted that he felt he possessed the credentials necessary to manage any company. In his new role, he was "confronted with problems of which I had no experience: Copyright and performing rights; Marconi patents; associations of concert artists, authors, playwrights, composers, music publishers, theatre managers, wireless manufacturers.". Slowly but surely, Reith began to advance into the unknown medium of public radio transmission, organising, experimenting and innovating. Realising the almost unlimited possibilities of broadcasting, and that it must eventually become a public service, he began to shape his organisation in that direction.

The two of the main objects of Reith's policy were to establish the independence of the BBC from any form of interference and to build an unassailable programme. In 1925 the Government appointed a committee under the chairmanship of Lord Crawford to consider the future of British broadcasting, where Reith prepared a plan for a public broadcasting service. According to his plans, news presentations would always be of the highest quality, and Sunday observance was strictly enforced. When the General Strike broke out in 1926, and the value of broadcasting as a governmental and political instrument became apparent, Winston Churchill and others in the Government wanted to commandeer the organisation for the emergency. Reith refused to comply, maintaining the BBC's independence. He won the argument, but made an enemy of Churchill for years to come.

Actually, the BBC was part-share owned by a committee of members of the wireless industry. Although opposed by some (including in Government), the BBC became a corporation in 1927 and Reith was knighted the same year. Reith's autocratic approach became the stuff of BBC legend. His preferred approach was one of benevolent dictator, but with built-in checks to his power. In 1938, with his work for broadcasting completed and his ideals established as traditions, he resigned to become managing director of Imperial Airways. But, two years later, when Britain was at war, he left this post to become Minister of Information under Prime Minister Neville Chamberlain. When Churchill succeeded Chamberlain in May 1940, old animosities prevailed and he was quickly transferred, first to the Ministry of Transport and then to the Ministry of Works and Buildings. He was also elevated to the House of Lords, becoming Baron Reith of Stonehaven. After the war, his sense of purpose was revived in his chairmanships of the Commonwealth Telecommunications Board, from 1946 to 1950, and the Colonial Development Corporation, 1950 to 1959.

When the BBC introduced the Reith Lectures in 1947 it was honouring the Corporation's debt to the man whose far-sightedness and clarity of purpose in early British broadcasting had demanded technical inventiveness and social conscience in equal proportions. At the age of 81, John Reith died in Edinburgh after a fall in 1971.

This is a British Pathé newsreel of MS. Sir John Reith, Minister of Information speaking at the Cinematography Exhibitors Association in 1940.

References and Further Reading:
Related Articles at yovisto Blog:

If you like the daily blog posts of yovisto about the history of science, please support us by clicking on the amazon links and making your next amazon purchase via our offered links. Nevertheless, please do also support your local (real world) bookstore at the corner of the street.

Saturday, July 19, 2014

The Dancers of Edgar Degas

Ballet Class (1873)
by Edgar Degas
On July 19, 1834, French artist Edgar Degas was born, famous for his paintings, sculptures, prints, and drawings. He is especially identified with the subject of dance; more than half of his works depict dancers. He is regarded as one of the founders of Impressionism, although he rejected the term, and preferred to be called a realist.

Edgar Degas graduated from school in 1853 and turned his room into an artist's studio. Despite the fact, that he was expected to become a lawyer, Degas enrolled at the École des Beaux-Arts and studied drawing there with Louis Lamothe. The young artist traveled to Italy in 1856, where he lived with his aunt's family in Naples. In this period, Degas drew and painted numerous copies of works by Michelangelo, Raphael, Titian, and other Renaissance artists, but he usually selected from an altarpiece a detail that had caught his attention, a secondary figure, or a head which he treated as a portrait. After a three year stay in Italy, Degas moved into a Paris studio to begin painting "The Bellelli Family", one of his early masterpieces. However, the painting remained unfinished until 1867. The artist created several history paintings, like Young Spartans around 1860 or Scene of War in the Middle Ages, but unfortunately, they received only little attention.

After the Franco-Prussian War in 1870, Degas stayed in New Orleans, Louisiana, where he created A Cotton Office, the only painting that was purchased by a museum in his lifetime. Beginning from 1874, the artist depended for the first time in his life on sales of his artwork for income and in this period, he produced probably his greatest work. He joined the group that soon became known as the Impressionists. Together, they mounted eight art shows. However, Degas did not feel that he had much in common with the artists, painting landscapes outdoors such as Monet. Also he disliked being called an impressionist.

Degas started painting women at work including milliners and laundresses in the late 1860s, shifting from his initial forays into history painting to an original observation of contemporary life. Mlle. Fiocre in the Ballet La Source, exhibited in the Salon of 1868, was his first major work to introduce a subject with which he would become especially identified, dancers. In many subsequent paintings, dancers were shown backstage or in rehearsal, emphasizing their status as professionals doing a job. His interest in portraiture led him to study carefully the ways in which a person's social stature or form of employment may be revealed by their physiognomy, posture, dress, and other attributes. In his paintings of dancers and laundresses, he reveals their occupations not only by their dress and activities but also by their body type. His ballerinas exhibit an athletic physicality, while his laundresses are heavy and solid.

In his later years, the artist also developed a high interest for photography. He often took pictures of friends, mostly indoors, and other images depicted dancers and nudes. As the years passed however, Degas became more and more isolated. The Dreyfus Affair controversy brought his antisemitic leanings to the fore and he broke with all his Jewish friends. In later life, Degas regretted the loss of those friends. It is assumed that he ceased working in 1912. Edgar Degas passed away on September 27, 1917.

At yovisto, you can learn more about Edgar Degas' art in the short lecture on the Milliners.

References and Further Reading:
Related Articles in the Blog: