1906

Nobel Prize in Physics

J.J. Thomson

Thomson had discovered the electron in 1897 by showing that cathode rays were streams of particles lighter than any atom — a finding that required revising the definition of "atom," which had been assumed indivisible since the ancient Greeks. His Nobel Prize recognised the broader investigation of how electricity passes through gases, but the electron was what mattered, and everyone knew it.

Nobel Prize in Chemistry

Henri Moissan

Fluorine is the most reactive element on the periodic table, which is a polite way of saying it attacks almost everything including the experimenters. At least two chemists died attempting its isolation before Moissan succeeded in 1886 using electrolysis at extremely low temperatures. He also built an electric furnace capable of reaching 3,500°C, which proved useful for a number of other things chemistry needed doing.

Nobel Prize in Physiology or Medicine

Camillo Golgi · Santiago Ramón y Cajal

They were given the prize jointly and disagreed publicly in their Nobel lectures. Golgi believed the nervous system was a continuous network; Cajal, using Golgi's own silver-staining technique, had amassed evidence that it was composed of individual neurons. Cajal was right, as the twentieth century eventually confirmed. The staining method that made his work possible was named after the man who thought he was wrong.

Nobel Prize in Literature

Giosuè Carducci

Italy's first Nobel laureate was a classicist-poet who had spent his career wrestling Italian verse into new forms and his academic career provoking his colleagues. He had also written an ode in praise of Satan as a young man, which the committee either forgave or admired. He was 71 and too ill to travel to Stockholm.

Nobel Peace Prize

Theodore Roosevelt

Roosevelt mediated the peace negotiations that ended the Russo-Japanese War at Portsmouth, New Hampshire in 1905, producing a settlement that surprised most observers by actually holding. He was the first American to win a Nobel Prize of any kind, and characteristically donated the prize money to a foundation promoting industrial peace.

Nernst heat theorem / third law of thermodynamics

Walther Nernst

Nernst proposed that as a system approaches absolute zero, the changes in entropy for any process approach zero as well — meaning that absolute zero is a limit you can approach but never quite reach, and that the entropy of a perfect crystal at absolute zero is exactly zero. This became the third law of thermodynamics, completing a set that had taken the better part of a century to assemble.

Alois Alzheimer's first description of Alzheimer's disease

Alois Alzheimer

On 3 November, Alzheimer presented the case of Auguste Deter — a 51-year-old woman who had suffered severe memory loss, confusion, and behavioural changes before her death — to a meeting of German psychiatrists in Tübingen. The post-mortem brain showed amyloid plaques and neurofibrillary tangles. The audience asked almost no questions, and Alzheimer's paper sank without much notice until his colleague Emil Kraepelin named the disease after him in 1910.

Lee de Forest invents the triode (Audion) vacuum tube

Lee de Forest

A two-element vacuum tube could detect radio signals. De Forest added a third electrode — a grid — and found that small voltages applied to it could control large currents passing through the tube. The device could amplify. This single addition made long-distance radio telephony possible, and later underpinned every piece of electronic equipment built until the transistor appeared forty years later.

Mikhail Tsvet develops and names chromatography

Mikhail Tsvet

Tsvet was trying to separate the pigments in plant leaves — chlorophylls and xanthophylls — and found that if he poured a solution through a column of calcium carbonate, the different compounds travelled at different speeds and separated into distinct coloured bands. He named the technique chromatography, from the Greek for colour-writing. It is now among the most widely used analytical methods in chemistry and biology.

Ejnar Hertzsprung distinguishes giant and dwarf stars

Ejnar Hertzsprung

Two stars can be the same colour — the same temperature, the same spectral type — and yet one may outshine the other by a factor of thousands. Hertzsprung recognised that colour and luminosity were independent properties, and that stars fell into two broad populations: giants and dwarfs. The diagram that bears his name, mapping these relationships for thousands of stars at once, would become one of the most illuminating pictures in astronomy.

Reginald Fessenden transmits first human voice over wireless

On Christmas Eve, ships' radio operators at sea near the New England coast were startled to hear, through their Morse-code receivers, a human voice reading from the Gospel of Luke, followed by a violin solo. Reginald Fessenden was broadcasting from Brant Rock, Massachusetts, using amplitude modulation — the principle that would underlie AM radio for the next century.

Frederick Hopkins begins experimental work on accessory food factors

Hopkins fed rats a diet of purified proteins, carbohydrates, and fats — everything nutritional science of the day considered sufficient — and the rats sickened and died. When he added small amounts of milk, they recovered. Something in food beyond the known macronutrients was essential for life. He called them accessory food factors; within a decade they would be called vitamins.

San Francisco earthquake scientific monitoring

The earthquake of 18 April — magnitude 7.9, followed by fires that burned for three days — killed an estimated three thousand people and destroyed much of the city. It also generated the most detailed seismological records gathered to that point, forcing American geologists to take earthquake science seriously as a discipline rather than an occasional curiosity.

Death of Pierre Curie

Pierre Curie

Pierre Curie was killed on 19 April when he slipped on a rainy Paris street and fell under the wheels of a horse-drawn wagon. He was 46. His death came at the height of his powers, and left Marie Curie to continue their work alone — which she did, for another 28 years.