January 20 is the birthday of Alexandre-Emile Béguyer de Chancourtois. Béguyer de Chancourtois was a French geologist who was the first to organize the elements on a chart by increasing atomic weights.
In 1860, chemists had a conference in Germany that produced a list of precise measurements of atomic weights of elements. These weights were based on setting the mass of oxygen at 16. De Chancourtois got the idea to plot these weights on a graph. The vertical column counts off mass in increments of one. The horizontal column counts across to 16. This puts each element along a diagonal line. On its own, this graph is basically useless. The trick occurs when you wrap this graph around a cylinder with a diameter equal to sixteen units on his graph. Now the elements line up in vertical rows with other elements with similar chemical properties. This gave the impression of the properties of elements had recurring properties or “periodicity”.
De Chancourtois called his graph vis tellurique or telluric spiral because tellurium was in the center of his spiral. He presented his work to the French Academy of Sciences, who in turn, published his paper in their journal. Unfortunately, they left out his graph and the description was difficult to understand. The paper was mostly ignored. The graph was republished in a geology journal later and did not attract the attention of the rest of the chemical world. His discovery finally would get more attention ten years later when Mendeleev published his well known periodic table of the elements.
Notable Science History Events for January 20
1931 – David Morris Lee was born.
Lee is an American physicist who shares the 1996 Nobel Prize in Physics with Robert C. Richardson and Douglas Osheroff for the discovery of the superfluid state of helium-3. The superfluid state occurs when the temperature of liquid helium approaches absolute zero and the viscosity suddenly becomes zero.
1930 – Edwin Eugene Aldrin, Jr. was born.
“Buzz” Aldrin is an American mechanical engineer and astronaut who was part of the Apollo 11 Moon landing. He was the second person to walk on the Moon as the Lunar Module pilot with Neil Armstrong. Prior to his NASA career, he served as a combat and test pilot for the US Air Force.
1901 – Zénobe-Théophile Gramme died.
Gramme was a Belgian electrical engineer who invented the Gramme dynamo. The Gramme dynamo was the first large-scale direct current (DC) generator used for commercial purposes. Gramme later discovered that his dynamo would act as an electric motor when connected to an electric current and would supply useful amounts of torque. These motors were the beginning of industrial electric motor use.
1820 – Alexandre-Emile Béguyer de Chancourtois was born.
1775 – André-Marie Ampère was born.
Ampère was a French physicist and mathematician who was the founder of the study of electrodynamics. He described how two wires carrying current will either repel or attract each other depending on if the current is running in the same or opposite direction in both wires. The SI unit of current is named in his honor.
1624 – Simon Marius was born.
Marius was a German astronomer who was one of the first to use a telescope. He had a dispute with Galileo for priority of the discovery of Jupiter’s four largest moons. He did not receive the credit, but his names: Io, Europa, Calisto, and Ganymede are still used today. He also recorded observations of the ‘nebula’ Andromeda noting it got brighter in the center than the edges. Today, we know Andromeda is a nearby galaxy.