JJ Thomson took science to new heights with his 1897 discovery of the electron – the first
He also found the first evidence that stable elements can exist as isotopes and invented one of the most powerful tools in analytical chemistry – the mass spectrometer.
Joseph John Thomson was born on December 18, 1856 in Manchester, England, UK. His father, Joseph James Thomson, ran a specialist bookshop that had been in his family for three generations. His mother, Emma Swindells, came from a family that owned a cotton company.
Even as a young boy, Joey, who would later be known as J. J., was deeply interested in science. At age 14 he became a student at Owens College, the University of Manchester, where he studied mathematics, physics, and engineering.
A shy boy, his parents hoped he would become an apprentice engineer with a locomotive
company. These hopes were dashed with the
death of his father when J. J. was 16. The fees for engineering apprenticeships were high, and
his mother could not afford them.
This misfortune ultimately benefited science because J. J. needed to find funding to continue his education. In 1876, age 19, he won that funding, not in engineering, but in
mathematics at the University of Cambridge.
Four years later he graduated with high honors.
Thomson devised better equipment and methods than had been used before. When he passed the rays through the vacuum, he was able to measure the angle at which they were deflected and calculate the ratio of the electrical charge to the mass of the particles.
He discovered that the ratio was the same regardless of what type of gas was used, which led him to conclude that the particles that made up the gases were universal.
Thomson continued studying at Cambridge and in 1882 he won the Adam’s Prize, one of the university’s most sought after mathematics awards. In 1883, he earned a master’s degree in mathematics.
J.J. Thomson is a name that will always be connected with the "discovery" of the electron. Yet, others had done research similar to that of Thomson and came to many of the same conclusions before he did. The name "electron" was not given by Thomson himself, but by George Johnstone Stoney, in 1894.
Stoney had concluded that electricity must have a particulate nature, based on electrochemical studies. That Stoney's electron and Thomson's particle of electricity were identical soon became evident, and Stoney's name was used for Thomson's discovery too.
In 1890, he married Rose Elisabeth, daughter of Sir George E. Paget, K.C.B. They had one son, now Sir George Paget Thomson, Emeritus Professor of Physics at London University, who was awarded the Nobel Prize for Physics in 1937, and one daughter. He died in Cambridge on August 30, 1940, and is buried in Westminster Abbey near two other influential scientists: Isaac Newton and Charles Darwin.
Thomson had the insight to understand the run of experiments that were required to pin down the particulate nature of electricity, which is why he was given much-deserved credit for the discovery. Yet, he was as good a mentor as he was a scientist, and perhaps his best student was Ernest Rutherford, who went on to make many discoveries of his own.
The chain of investigation linking one generation of scientists with the next is an important but generally overlooked characteristic of the scientific method