Thứ Sáu, 1 tháng 11, 2013

 

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Date of Issue : 16 October 2013

Czech Post issued a postage stamp commemorating the inventor of Contact lenses, Prof.  Otto Wichterle.   This world-renowned scientist became famous for silon and soft contact lenses which he invented.


He was born on 27 October 1913 into a rich business family in Prostějov. At the age of 6, he almost died from a persistent fever. He was therefore home-schooled. After his recovery he went directly to the fifth year and, at the young age of 9, he was admitted to a state-run grammar school. He graduated with honours. He wanted to study mathematics and physics at university, his was choice was therefore between mechanical engineering and chemistry. He decided to study chemical technology engineering at the Czech Technical University in Prague.


He wrote his thesis under the tutelage of Professor Votoček, an important chemist and co-author of the Czech chemical nomenclature. His idea of a scientific study free of any commercial or political interests had a strong impact on Wichterle. Wichterle continued his studies at the school of medicine, which offered him the possibility to join a new discipline, biochemistry.


Following the events on 17 November 1939, when all Czech universities were closed by the Nazis, he took up a job in Baťa Shoe Company’s chemical research laboratory. He began with the research of Nylon 66, a synthetic polymer which was not suitable for the fibre spinning process. His previous experience helped him find a treatment which made nylon suitable for fibre applications. This led to the industrial production of silon, a synthetic material used mainly in men’s socks and women’s tights.


But his best known invention are gel contact lenses. The start-up of their production suffered from many problems, inaccuracies and low yields. In 1961, Wichterle used a Merkur modelling kit for children and a gramophone motor to build a prototype of the production machine; the process was eventually simplified and ready for large-scale production. In 1965, his invention attracted large U.S. companies which started the production of contact lenses abroad.


Wichterle’s political neutrality caused him a lifetime of problems, especially during the communist regime. He had to wait until after 1989 for well-deserved honours and awards. In 1990, he was elected President of the Czechoslovak Academy of Sciences. He remained in the office until the split of Czechoslovakia in 1993. In 1993, Charles University awarded him a degree honoris causa and a planet in our solar system was named after him. Starting from 2002, talented scientists younger than 35 years may receive an Otto Wichterle Award granted by the Academy of Sciences of the Czech Republic. He died on 18 August 1998 in Stražicko.

200th anniversary of the Battle of Leipzig

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Date of Issue : 2 October 2013

The Battle of Leipzig, fought on 16-19 October 1813 in Germany, was the largest and decisive battle of the Napoleonic wars. It was a clash between the army of the French Emperor Napoleon and the allied armies of Austria, Prussia, Russia and Sweden. The grandiose battle involved over half a million soldiers and more than two thousand cannons, making it the largest battle in the world prior to World War I. The coalition army, under the command of Karl von Schwarzenberg and several other princes, had over 300,000 troops. It outnumbered the Napoleon’s army of less than 200,000 troops.


Both armies achieved no success on the first day of the battle which ended in a stalemate. The second day was used by both armies to reorganise their forces and wait for reinforcements. The French received only 14,000 troops as reinforcements; the coalition was strengthened by the arrival of 145,000 troops. On the third day, the coalition army launched a huge assault from all sides. In over nine hours of fighting, both sides suffered heavy casualties. Napoleon saw that the battle was a lost cause and he began to withdraw his army across the river Elster. However, because of a mistake of his own commanders, the bridge over the Elster which was the only exit route was destroyed before the entire army was able to cross the river. Those who survived began to flee towards France. Shortly afterwards, Napoleon was exiled to the island of Elba. The defeat dealt a harsh blow against Napoleon himself, who was finally defeated two years later in the Battle of Waterloo.


The Czech troops, who defeated Napoleon in the battle of Chlumec nearby Ústí nad Labem prior to the battle of Leipzig, considered the victory as their own triumph. Even more so because one of the commanders-in-chief of the Allied army, field marshal Karl von Schwarzenberg, was considered as a Czech prince. None of the battles fought before or after the Leipzig campaign involved so many Czech high ranking commanders including the highest ones (John Joseph Wenceslaus, Count Radetzky of Radetz was Schwarzenberg’s chief of staff). A memorial for the battle, the “Völkerschlachtdenkmal”, was unveiled in 1913 in Leipzig.

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