Site is under maintenance mode. Please wait few min!

John Dalton

John Dalton Photo

John Dalton was born in 1766 in Eaglesfield, England. He was an English meteorologist and chemist known for establishing and developing modern atomic theory. Dalton was born to a Quaker family; Quaker families were regarded as dissenters by the established Church of England. Dalton and his brother were born color blind which exemplified his research into color blindness. His father was a weaver, which meant that it afforded the family a modest living. As a child, Dalton attended a Quaker school in Cumberland. Given the family’s dwindling means of subsistence, he started helping as a teacher at age 12 at the same school and then served as an assistant at a Quaker boarding school in Kendal. At 18, Dalton was appointed principal of the school and as early as 27 he started teaching mathematics and philosophy at the New College in Manchester.

Dalton’s primary interest in meteorology came with his encounter with a prominent Eaglesfield Quaker, Elihu Robinson who was a meteorologist and instrument maker at Kendal. Dalton acquired most of his knowledge in mathematics and science from Robinson and recorded several of his observations including instrument making and recording daily weather.

While Dalton was teaching at New College in Manchester he put together his first book through a collection of essays on meteorological topics based on his own observations along with those of his friends John Gough and Peter Crosthwaite. The publication entitled Meteorological Observations and Essays was published in 1793.

Approximately a year after Dalton had set fort in Manchester, in 1794 he was elected a member of the Manchester Literary and Philosophical Society where he submitted his first paper on color blindness – “Extraordinary facts relating to the vision of colors”. Afflicted with the condition himself, Dalton postulated that shortage in color perception was caused by discoloration of the liquid medium of the eyeballs. Dalton also suggested that the condition was hereditary since other members of his family suffered from the same condition as well. Over time, Dalton’s theory of color blindness was nullified. Yet, since he was first to bring the condition to light and conduct research upon it, the condition came to be identified as Daltonism. In 1800, when Dalton was 34, New College’s deteriorating financial standing resulted in Dalton’s resignation and then on he became a private tutor in mathematics and natural philosophy.

During his lifetime, Dalton published papers covering a wide array of topics such as heat conduction, gas expansion by heat, the properties of light, the aurora borealis, and meteorology.

Through his interest in meteorology, Dalton arrived at his research on gases and atoms. According to Dalton, the chemical construct of gas didn’t make it a solvent as was the widely held belief. Rather, the chemical makeup of air was a mechanical system composed of small individual particles that used pressure applied by each gas independently.

Based on his continued research work on gases, Dalton published his Law of Partial Pressures in 1803, which states that in a mixture of non-reacting gases, the total gas pressure is equal to the sum of the partial pressures of the individual gases. This finding garnered him great recognition as a scientist and Dalton was invited to deliver lectures at the Royal Institution in London.

After declaring his views in gases, Dalton went on to another area of atmospheric studies that intrigued him – atoms. He asserted that all matter was made up of hard round particles, which he called ‘atoms’, and that each type of atom, or element, such as hydrogen, oxygen, nitrogen, etc., differed only by its weight. In 1808, through his book A New System of Chemical Philosophy, Dalton aimed to expand on his idea that atoms of different elements could be universally distinguished based on their varying atomic weights. Thus came the Atomic Theory, rendering Dalton the first scientist to explain the behavior of atoms in terms of the measurement of weight. Dalton eventually composed a table listing the atomic weights of all known elements.

In 1822, John Dalton was elected member of the Royal Society and in 1826, he was awarded the Society’s Royal Medal for his Atomic Theory.

Write About John Dalton