Airflow across a wing
"It is often said that the lift on a wing is generated because the flow moving over the top surface has a longer distance to travel and therefore needs to go faster. This common explanation is actually wrong." Here, aerodynamics expert Professor Holger Babinsky from the University of Cambridge's Department of Engineering debunks a popular, yet misleading, explanation of how wings lift. For more information, read the accompanying story published by the University of Cambridge http://www.cam.ac.u
The Empire That Was Russia
Offers photographs of the Russian Empire on the eve of World War I and the coming revolution. Medieval churches and monasteries, railroads and factories, and daily life and work of Russia's diverse population are among the subjects. The photos were taken by Sergei Mikhailovich Prokudin-Gorskii (1863-1944), who, in the early 1900s, formulated a plan for a photographic survey of the Russian Empire that won the support of Tsar Nicholas II.
Rivers, Edens, Empires: Lewis & Clark and the Revealing of America
Looks at historical maps, relations with Indians, and expedition artifacts -- the blunderbuss, Jefferson's secret message to Congress, his instructions for Meriwether Lewis, and speeches. Subsequent expeditions of America are also examined, including those by Lieutenant Zebulon Pike, Thomas Freeman, Major Stephen Long, Father de Smet, and John Fremont.
Presents the most significant documents from our fourth President, James Madison. Most relate to two events in which Madison played a key role: the drafting and ratification of the Constitution (1787-8) and the introduction in the First Federal Congress of the amendments (1789) that became the Bill of Rights. Other documents relate to the freedom of religion and the burning of Washington, D.C., by the British in 1814 -- perhaps the major embarrassment of Madison's career.