Four-year-old Michael Finder of East Germany is tossed by his father into a net held by firemen across the border in West Berlin. The apartments were in East Berlin while their windows opened into West Berlin; October 7th, 1961
Public execution of Roman Catholic Priests and other Polish Civilians in Bydgoszcz’s Old Market Square; September 9th, 1939
Colored photo of the cascades of Bergpark Wilhelmshöhe, a landscape park in Kassel, Germany, and a future UNESCO World Heritage Site. Cascades are created from the 92,000 gallons of water flowing through the then 200-year-old hydro-pneumatic devices; ca. 1890 – 1905
Inflating cow skins to use as boats for crossing the swift Himalayan River Sutlej, northern India; ca. 1903
Stereoscopic photograph of inflated bullock skin boat, or dreas, at the side of the river Sutlej, in Himachal Pradesh, taken by James Ricalton in c. 1903, from The Underwood Travel Library: Stereoscopic Views of India. This image is described by Ricalton in ‘India Through the Stereoscope’ (1907): “I have crossed the river several times on these inflated bullock-skins…The drea-man, after inflating the skin as you see them doing here, places it on the water and places himself on his stomach athwart the skin with his feet in the water; he holds a short paddle in his hands. The intending passenger sits erect, astride the drea-man…You have observed how the skin for this purpose is taken from the animal in one piece and how all openings in the skin are closed except in one leg which is kept open for inflation…These drea-wallahs can drive the skins across the river during high floods when the best swimmer would be helpless in the powerful current.” One of a series of 100 photographs that were supposed to be viewed through a special binocular viewer, producing a 3D effect. The series was sold together with a book of descriptions and a map with precise locations to enable the ‘traveller’ to imagine that he was really ‘touring’ around India. Stereoscopic cameras, those with two lenses and the ability to take two photographs at the same time, were introduced in the mid 19th century and revolutionised photography. They cut down exposure time and thus allowed for some movement in the image without blurring as subjects were not required to sit for long periods to produce sharp results.
B-17G ‘Wee Willie’ shot down in a sortie over a marshalling yard in Stendal, Germany. Of the crew of 9 only the pilot survived; ca. April 8th, 1945
Wee Willie was shot down just 31 days before the end of the Second World a in Europe, and was the second to last B-17 lost by the 91st Bomb Group before the end of the war. The crash was described as follows by an eyewitnesses:
“We were flying over the target at 20,500 feet [6,248 meters] altitude when I observed aircraft B-17G, 42-31333 to receive a direct flak hit approximately between the bomb bay and #2 engine. The aircraft immediately started into a vertical dive. The fuselage was on fire and when it had dropped approximately 5,000 feet [1,524 meters] the left wing fell off. It continued down and when the fuselage was about 3,000 feet [914.4 meters] from the ground it exploded and then exploded again when it hit the ground. I saw no crew member leave the aircraft or parachutes open.”
The pilot managed to escape and spend the rest of the war as POW.
The wreck of the 1908 Wright Flyer that seriously injured Orville Wright and killed Lt. Thomas E. Selfridge, the first person to die as the result of an airplane accident; September 17th, 1908
During flight trials to win a contract from the U.S. Army Signal Corps, pilot Orville Wright and passenger Lt. Thomas Selfridge crash in a Wright Flyer at Fort Myer, Virginia. Wright is injured, and Selfridge becomes the first passenger to die in an airplane accident.
After Wilbur and Orville Wright made their historic first-ever airplane flight Dec. 17, 1903, they spent the next few years largely in seclusion developing their new invention. By the end of 1905 their interest in aviation had changed from curiosity and the challenge of flying, to the business of how to turn aviation into an industry: They were looking for a business model.
Unfortunately their first attempts to attract the United States government to the idea of using airplanes were turned down. The military just didn’t see how the airplane could be used in any practical way.
For two-and-a-half years the Wright brothers did not fly. They continued to work on their airplane, but put more and more time into building the business. Eventually they were able to attract interest from both the French and British governments, but by 1907 they still did not have any firm contracts.
But the Wright brothers were awarded two contracts in 1908: one from the U.S. Army and the other from a French business. The Army contract was for a bid to fly a two-man “heavier-than-air” flying machine that would have to complete a series of trials over a measured course. In addition to the $25,000 (about $600,000 in today’s buying power) bid, the brothers would receive a $2,500 bonus for every mile per hour of speed faster than 40 mph. No supersonic stealth fighters just yet.
Because they had not flown since October 1905, the brothers returned to Kitty Hawk to test their new controls to be used on the Wright Flyer in the Army flight trials. Despite some difficulty getting used to the new controls, both brothers managed to get some practice flying in during the stay in North Carolina.
Wilbur was in France during the summer of 1908 demonstrating the new Wright Flyer to Europeans (video). Orville remained in the United States and on Sept. 3 made his first flight at Fort Myer, where the Army trials were set to begin.
The flight tests set out by the Army required the airplane to carry two people for a set duration, distance and speed. There was a committee of five officers to evaluate the Wright Flyer’s performance, including the 26-year-old Selfridge.
Selfridge was a member of the Aerial Experiment Association and had designed the group’s first powered airplane. The Red Wing first flew on March 12, 1908, but crashed and was destroyed on its second flight a few days later.
During the first two weeks of September Orville made 15 flights at Fort Myer. He set three world records Sept. 9, including a 62-minute flight and the first public passenger flight. By Sept. 12 Orville had flown more than 74 minutes in a single flight and carried Maj. George Squier for more than 9 minutes in one flight.
On Sept. 17 Orville was flying Selfridge on another of the test flights. Three or four minutes into the flight, a blade on one of the two wooden propellers split and caused the engine to shake violently. Orville shut down the engine but was unable to control the airplane.
The propeller had hit a bracing wire and pulled a rear rudder from the vertical position to a horizontal position. This caused the airplane to pitch nose-down, and it could not be countered by the pilot.
The Wright Flyer hit the ground hard, and both men were injured. Orville suffered a fractured leg and several broken ribs. Selfridge suffered a fractured skull and died in the hospital a few hours later.
Despite the crash, and the first passenger death in an airplane, the Army was significantly impressed with the Wright Flyer and allowed the brothers to complete the trials the following year. They were awarded the contract. Along with success in France, the Wright brothers were well on their way to establishing what would become one of the most successful aviation companies during the early days of flying.
Because of the crash, the first Army pilots were required to wear helmets similar to early football helmets in order to minimize the chance of a head injury like the one that killed Selfridge.
Though the early days of aviation continued to be full of danger, airplane travel today is statistically one of the safest modes of transportation based on passenger miles traveled. Between 1995 and 2000 there were about 3 deaths per 10 billion passenger miles flown.
Back to front, left to right:
Back: Auguste Piccard, Émile Henriot, Paul Ehrenfest, Édouard Herzen, Théophile de Donder, Erwin Schrödinger, JE Verschaffelt, Wolfgang Pauli, Werner Heisenberg, Ralph Fowler, Léon Brillouin.
Middle: Peter Debye, Martin Knudsen, William Lawrence Bragg, Hendrik Anthony Kramers, Paul Dirac, Arthur Compton, Louis de Broglie, Max Born, Niels Bohr.
Front: Irving Langmuir, Max Planck, Marie Curie, Hendrik Lorentz, Albert Einstein, Paul Langevin, Charles-Eugène Guye, CTR Wilson, Owen Richardson.
The scientists on the picture:
• Auguste Piccard designed ships to explore the upper stratosphere and the deep seas (bathyscaphe, 1948).
• Emile Henriot detected the natural radioactivity of potassium and rubidium. He made ultracentrifuges possible and pioneered the electron microscope.
• Paul Ehrenfest remarked (in 1909) that Special Relativity makes the rim of a spinning disk shrink but not its diameter. This contradiction with Euclidean geometry inspired Einstein’s General Relativity. Ehrenfest was a great teacher and a pioneer of quantum theory.
• Edouard Herzen is one of only 7 people who participated in the two Solvay conferences of 1911 and 1927. He played a leading role in the development of physics and chemistry during the twentieth century.
• Théophile de Donder defined chemical affinity in terms of the change in the free enthalpy. He founded the thermodynamics of irreversible processes, which led his student Ilya Prigogine (1917-2006) to a Nobel prize.
• Erwin Schrödinger matched observed quantum behavior with the properties of a continuous nonrelativistic wave obeying the Schrödinger Equation. In 1935, he challenged the Copenhagen Interpretation, with the famous tale of Schrödinger’s cat. He shared the nobel prize with Dirac.
• Jules Emile Verschaffelt, the Flemish physicist, got his doctorate under Kamerlingh Onnes in 1899.
• Wolfgang Pauli formulated the exclusion principle which explains the entire table of elements. Pauli’s sharp tongue was legendary; he once said about a bad paper: “This isn’t right; this isn’t even wrong.”
• Werner Heisenberg replaced Bohr’s semi-classical orbits by a new quantum logic which became known as matrix mechanics (with the help of Born and Jordan). The relevant noncommutativity entails Heisenberg’s uncertainty principle.
• Sir Ralph Howard Fowler supervised 15 FRS and 3 Nobel laureates. In 1923, he introduced Dirac to quantum theory.
• Léon Nicolas Brillouin practically invented solid state physics (Brillouin zones) and helped develop the technology that became the computers we use today.
• Peter Debye pioneered the use of dipole moments for asymmetrical molecules and extended Einstein’s theory of specific heat to low temperatures by including low-energy phonons.
• Martin Knudsen revived Maxwell’s kinetic theory of gases, especially at low pressure: Knudsen flow, Knudsen number etc.
• William Lawrence Bragg was awarded the Nobel prize for physics jointly with his father Sir William Henry Bragg for their work on the analysis of the structure of crystals using X-ray diffraction.
• Hendrik Kramers was the first foreign scholar to seek out Niels Bohr. He became his assistant and helped develop what became known as Bohr’s Institute, where he worked on dispersion theory.
• Paul Dirac came up with the formalism on which quantum mechanics is now based. In 1928, he discovered a relativistic wave function for the electron which predicted the existence of antimatter, before it was actually observed.
• Arthur Holly Compton figured that X-rays collide with electrons as if they were relativistic particles, so their frequency shifts according to the angle of deflection (Compton scattering).
• Louis de Broglie discovered that any particle has wavelike properties, with a wavelength inversely proportional to its momentum (this helps justify Schrödinger’s equation).
• Max Born’s probabilistic interpretation of Schrödinger’s wave function ended determinism in physics but provided a firm ground for quantum theory.
• Irving Langmuir was an American chemist and physicist. His most noted publication was the famous 1919 article “The Arrangement of Electrons in Atoms and Molecules”.
• Max Planck originated quantum theory, which won him the Nobel Prize in Physics in 1918. He proposed that exchanges of energy only occur in discrete lumps, which he dubbed quanta.
• Niels Bohr started the quantum revolution with a model where the orbital angular momentum of an electron only has discrete values. He spearheaded the Copenhagen Interpretation which holds that quantum phenomena are inherently probabilistic.
• Marie Curie was the first woman to earn a Nobel prize and the first person to earn two. In 1898, she isolated two new elements (polonium and radium) by tracking their ionizing radiation, using the electrometer of Jacques and Pierre Curie.
• Hendrik Lorentz discovered and gave theoretical explanation of the Zeeman effect. He also derived the transformation equations subsequently used by Albert Einstein to describe space and time.
• Albert Einstein developed the general theory of relativity, one of the two pillars of modern physics (alongside quantum mechanics).He is best known in popular culture for his mass–energy equivalence formula (which has been dubbed “the world’s most famous equation”). He received the 1921 Nobel Prize in Physics “for his services to theoretical physics, and especially for his discovery of the law of the photoelectric effect”.
• Paul Langevin developed Langevin dynamics and the Langevin equation. He had a love affair with Marie Curie.
• Charles-Eugène Guye was a professor of Physics at the University of Geneva. For Guye, any phenomenon could only exist at certain observation scales.
• Charles Thomson Rees Wilson reproduced cloud formation in a box. Ultimately, in 1911, supersaturated dust-free ion-free air was seen to condense along the tracks of ionizing particles. The Wilson cloud chamber detector was born.
• Sir Owen Willans Richardson won the Nobel Prize in Physics in 1928 for his work on thermionic emission, which led to Richardson’s Law.