John Dalton

NAME John Dalton

WHAT FAMOUS FOR John Dalton is primarily famous for his groundbreaking work in the field of chemistry and physics, most notably for developing the modern atomic theory. He also conducted pioneering research on color blindness, a condition he himself had, which is still sometimes referred to as "Daltonism."

BIRTH John Dalton was born on September 5 or 6, 1766, in Eaglesfield, a small village near Cockermouth in Cumberland, England (now Cumbria). The exact date remains uncertain, as his name was curiously not entered in the Quaker register.

FAMILY BACKGROUND Dalton came from a modest Quaker family. His father, Joseph Dalton, was a weaver who owned a small house and land, though the family was relatively poor. His mother, Deborah Greenup, came from a more prosperous local Quaker family and was described as a woman of strong character and intelligence. 

John was the youngest of three children who survived to adulthood, with siblings Jonathan and Mary. The Daltons belonged to the Society of Friends (Quakers), which significantly influenced John's values, emphasizing simplicity, hard work, and education.

CHILDHOOD Dalton's childhood was marked by early intellectual promise despite the family's modest circumstances. As a small child, he worked in the fields with his older brother and helped his father in their cloth-weaving shop. Though they were poor, Dalton was fortunate to attend a nearby Quaker school run by John Fletcher at Pardshaw Hall. In an era when only about one out of every 200 people could read, Dalton proved to be an exceptional student with a natural love of learning. 

Dalton's family was too poor to support him for long, and aged 10, he entered the service of Elihu Robinson, a wealthy Quaker gentleman with scientific interests who became an important early mentor.

EDUCATION Though Dalton's formal education ended when he was 10,  his education continued informally under several influential mentors.  Elihu Robinson taught him mathematics and interested him in meteorological problems. Later, at Kendal, John Gough, a blind classics scholar and natural philosopher, became another significant mentor, teaching Dalton Latin, Greek, and encouraging his scientific interests. 

Much of Dalton's extensive knowledge was self-taught, demonstrating his remarkable dedication to learning. As a Quaker, he was barred from attending Oxford and Cambridge universities, which excluded religious dissenters.

CAREER RECORD 1778 Aged 12, Dalton began teaching at the local Quaker school in Eaglesfield.

1781 When Quaker schoolmaster John Fletcher retired, 15-year-old Dalton joined his brother Jonathan in running a school in Kendal, about 45 miles from home. By age 19, he had become the school’s principal, continuing in the role until age 26.

1793 Dalton moved to Manchester to become a tutor of mathematics and natural philosophy at New College, a dissenting academy for students excluded from Oxford and Cambridge for religious reasons.

1800 After New College closed due to financial difficulties, Dalton worked as a private tutor in science and mathematics, while continuing his research. He also lectured at the Pine Street School of Medicine for two years, teaching pharmaceutical chemistry.

1801–1803 He conducted pioneering studies on colour blindness (later called “Daltonism”) and began formulating his atomic theory, proposing that all matter is composed of indivisible atoms based on experimental observation rather than philosophical speculation.

1803 On September , Dalton began using symbols to represent the atoms of different elements — the first such system in modern chemistry.

1808 He published A New System of Chemical Philosophy, laying out his atomic theory in detail and revolutionising the field of chemistry.

1822 Elected a Fellow of the Royal Society, Dalton gained recognition across Europe for his contributions to science.

APPEARANCE John Dalton was described as a plain, unassuming man of medium height with a robust and muscular build and a prominent nose. Contemporary accounts characterize him as having a strong, analytical mind but an unprepossessing physical appearance. He was sometimes perceived as unattractive and uncouth in society, occasionally presenting an appearance of moroseness to strangers. (1)

Dalton by Thomas Phillips, 1835

FASHION Dalton maintained the simple dress consistent with his Quaker faith throughout his life. 

His colour blindness occasionally led to amusing fashion mishaps. The most famous incident occurred when he bought what he thought were sombre blue stockings for his mother, only to discover they were bright red - shocking for Quaker sensibilities. Another notable incident involved him nearly ordering a complete suit of bright scarlet cloth for a trip to Paris, thinking it was appropriate dark material, until his tailor intervened by pointing out it was used only for hunting coats. (2)

CHARACTER Dalton was amiable, straightforward, and unpretentious, embodying the Quaker values of simplicity, humility, and hard work throughout his life. Despite achieving scientific renown, he lived frugally and avoided the pursuit of wealth or luxury. Known for his industry, perseverance, and modesty, he combined deep philosophical thought with a vivid scientific imagination. 

He was not one for social gatherings and preferred to spend his time working in his laboratory or studying nature. To strangers, he could sometimes seem reserved or even brusque.  he was often content to work with rough, imprecise instruments, even when finer ones were within reach.

SPEAKING VOICE Dalton had a gruff voice and a curt manner of speaking. After suffering a stroke in 1837, his speech became impaired, leaving him with a speech impediment for the remainder of his life. Despite this impairment, he continued to present papers and conduct his scientific work.

SENSE OF HUMOUR Dalton possessed a dry sense of humour and was fond of making sly jokes, particularly from his position as President of the Manchester Literary and Philosophical Society. On one memorable occasion, when someone was reading a particularly meaningless paper, Dalton remarked in an audible whisper to the secretaries, "Well, this is a very interesting paper for those that take any interest in it".  (2)

RELATIONSHIPS Dalton never married, dedicating his life entirely to science and education. However, he maintained warm friendships with several women. He had a particularly close friendship with Miss Nancy Wilson, who died young, but whose memory he always cherished with affection. He also formed close friendships with Mademoiselle Clementine Cuvier, daughter of the celebrated naturalist. 

For nearly thirty years, he lived in the humble home of his friend, the Rev. William Johns, of Manchester, where he was treated as family. When asked why he never married, he replied that he never had time, though financial constraints likely also played a role.

MONEY AND FAME Despite his world-renowned scientific contributions, Dalton lived in relative poverty for most of his life. He had to support himself through teaching until he was 67 years old. His modest income came from private tutoring, with students paying weekly pence that totaled about five shillings. He was often content to work with rough, imprecise instruments, even when finer ones were within reach. The contrast between his fame and financial situation was striking - a distinguished French chemist who came to Manchester expecting to find Dalton at a great university instead found him in a clergyman's humble home in a back street, tutoring a boy in arithmetic. Only in 1836 did the government grant him a pension of £300 per year in recognition of his great work. 

He was consistently modest about his achievements and had difficulty accepting the numerous honours offered to him.

FOOD AND DRINK Dalton maintained simple eating habits consistent with his Quaker lifestyle. He typically came to dinner when it was nearly finished, likely to avoid spending too much time at meals and maximize his laboratory time. His supper often consisted of oatmeal porridge.

In experiments on himself, Dalton meticulously recorded his food and drink intake, including loaf bread, cheese, oat bread, meal, meat, potatoes, beer, boiled milk, and tea. He would measure his food intake and compare it to his body's waste production as part of his scientific observations.

MUSIC AND ARTS Dalton had little interest in music or the arts. He found them to be a distraction from his scientific work. As a Quaker, he would have been influenced by the Society of Friends' emphasis on simplicity and their general avoidance of elaborate artistic expressions or entertainment.

LITERATURE Dalton was well-read in scientific literature, from classical works by Boyle and Newton to contemporary writings by Claude Louis Berthollet and Humphry Davy. He contributed solutions to problems and answered questions in publications like The Ladies' Diary and the Gentleman's Diary during his years in Kendal. 

His own major published works included Meteorological Observations and Essays (1793) and his seminal A New System of Chemical Philosophy (1808-1827).

NATURE During his time in Kendal, Dalton studied the weather and nature around him extensively, collecting butterflies, snails, mites, and maggots. He began his meteorological diary in 1787 at age 21 and continued making daily weather observations for 57 years until the day before his death, recording more than 200,000 observations. This dedication to meteorological observation demonstrates his deep connection to natural phenomena and systematic approach to understanding the natural world.

He also enjoyed botany and often took long walks in the countryside.

HOBBIES AND SPORTS Dalton's primary recreation was playing bowls, which he enjoyed every Thursday afternoon at the "Dog and Partridge" tavern, located about three miles from central Manchester. He belonged to a bowling club that provided his main social outlet outside of scientific work. 

Image by Perplexity

He was also fond of long country walks and regularly walked the 40-mile journey from his home to Kendal, often preferring to walk rather than take other transportation. These activities provided his only respite from his otherwise intensive scientific work schedule. (2)

ATOMIC THEORY At the dawn of the 19th century, when most people still thought of matter as a kind of invisible mush, John Dalton strolled onto the scene with an idea that would change chemistry forever: atoms. Not just the philosophical musings of ancient Greeks, mind you, but proper, experimentally grounded, measurable things.

Dalton had been poking about in the atmosphere for years—measuring, weighing, jotting down notes on how gases mix, and wondering why they don’t separate like oil and water. He was intrigued by why oxygen doesn’t just float obligingly to the top of the air and leave nitrogen below. His meteorological tinkering led him to think about the very building blocks of matter.

He also had some heavyweight inspiration: Antoine Lavoisier’s law of conservation of mass, which says matter can’t just pop in or out of existence, and Joseph Proust’s law of definite proportions, which pointed out that chemical compounds always contain the same elements in the same ratios. Something, Dalton felt, had to explain these neat, numerical regularities.

In 1803, at a lecture in Manchester, Dalton unveiled his atomic theory to a polite but probably slightly baffled audience. He refined it in talks to scientific societies across England, and in 1808 published the whole thing in the first volume of A New System of Chemical Philosophy. The title might have sounded dry, but the content was dynamite for the chemistry world.

Various atoms and molecules as depicted in John Dalton's A New System of Chemical Philosophy

Dalton’s main points, stated plainly, were these:

All matter is made of tiny, indivisible, indestructible particles called atoms.

Atoms of the same element are identical in weight and properties.

Atoms of different elements have different weights and properties.

Atoms combine in simple, whole-number ratios to form compounds.

Chemical reactions rearrange atoms, but never create or destroy them.

He also hammered home that compounds are the result of atoms combining in fixed ratios—explaining not just one, but two chemical laws: definite proportions and multiple proportions.

For the first time, chemistry had a coherent, testable framework for explaining why substances behave the way they do. Dalton even took the bold step of assigning relative weights to known elements, setting the stage for the modern periodic table. Admittedly, he got a few things wrong—famously thinking water was OH, not H₂O—but his theory stuck, and it remains the backbone of chemistry.

In short, Dalton’s atomic theory marked the birth of modern chemistry. It turned an abstract, philosophical notion into something practical, measurable, and powerful enough to explain the very fabric of matter. And all this from a modest Quaker schoolteacher who, it seems, simply couldn’t stop asking “But why?”

SCIENCE AND MATHS Dalton's scientific work was groundbreaking across multiple fields. His most famous contribution was the development of modern atomic theory in 1803, proposing that all matter consists of indivisible atoms, with each element having atoms of unique mass. He published the first table of atomic weights and formulated key principles about chemical reactions. 

In physics, he developed Dalton's Law of Partial Pressures for gas mixtures. 

He conducted the first scientific study of colour blindness, leading to the condition being called "Daltonism". 

In meteorology, he kept detailed daily records for 57 years and rediscovered George Hadley's theory of atmospheric circulation. 

Despite being sometimes criticized as "a very coarse experimenter" by Humphry Davy, historians who have replicated his experiments have confirmed his skill and precision.

In mathematics, he made contributions to the study of logarithms and binomial series.

PHILOSOPHY & THEOLOGY Dalton remained a committed Quaker all his life, and his faith deeply coloured both the way he lived and the way he worked. He held a profound and genuine reverence for “the great Author of all things” and for the Scriptures, seeing no conflict between religious devotion and scientific inquiry. The Quaker ideals of simplicity, equality, and direct personal experience of the divine shaped his worldview, encouraging a plain, disciplined approach to life. 

Yet Dalton was also very much a man of his age, engaging with the philosophical debate over whether science should rely solely on observation or embrace explanatory theories. His atomic theory marked a turning point in this discussion—rooted in careful measurement, yet bold enough to offer a unifying framework for understanding the natural world.

POLITICS  Dalton was not politically active. His Quaker beliefs led him to avoid political life and military service. He was a pacifist and maintained a quiet, private existence

SCANDAL There are no known scandals associated with John Dalton. He lived a virtuous and respectable life.

MILITARY RECORD  As a Quaker, Dalton was a pacifist by religious conviction, and the Society of Friends traditionally refused military service. His contributions to society were entirely through science and education rather than military service.

HEALTH AND PHYSICAL FITNESS Dalton maintained good health for most of his life despite his intensive work schedule. However, his health declined in his later years. In 1837, at age 71, he suffered his first paralytic stroke (likely what we would now call a stroke), which affected his speech and left him with only partial use of his left side. A few months later, he had a second attack, from which he recovered reasonably well. Three months before his death in 1844, he suffered a third attack that further reduced his strength. Despite these health setbacks, he continued his scientific work until near the end of his life.

HOMES Dalton was born in a small thatched cottage in Eaglesfield, Cumberland. During his teaching years in Kendal, he lived at the school. 

After moving to Manchester in 1793, he initially had accommodation at New College. Later, for nearly thirty years, he lived in the humble home of his friend, the Rev. William Johns, occupying a single bedroom and being treated as family. This arrangement began by chance when Mrs. Johns invited him to live with them, and it developed into a lasting friendship characterized by mutual respect and affection. (2)

TRAVEL Dalton's travels were primarily for scientific purposes. In 1822, he visited Paris, where he met many distinguished scientists including Cuvier, Laplace, Gay-Lussac, Arago, and Biot. He gave lecture tours to many large towns in England following the publication of his atomic theory. 

Despite his modest circumstances, he "acquired a taste for travel" and met with scientists both at home and abroad. 

His regular travels included frequent walks between Manchester and Kendal, a distance of about 40 miles, which he often preferred to complete on foot.

DEATH John Dalton died on July 27, 1844, at his home in Manchester at the age of 78. On the evening before, he retired to bed after his usual supper of oatmeal porridge. The following morning, his servant spoke to him at about six o'clock, then left the room. When the servant returned half an hour later, he found Dalton in a state of insensibility. Dalton remained unconscious until his death later that day, passing away "imperceptibly as an infant sinking into sleep". Before his death, following his wishes, he donated his eyes to science for research into colour blindness.

He was given a public funeral, a rare honor, and was buried at Ardwick Cemetery. 

APPEARANCES IN MEDIA

Dalton's death and life were widely commemorated in the media of his time. The Illustrated London News covered his funeral procession in 1844. His funeral was perhaps the largest cortège ever held in Manchester's history up to that point, with 95 carriages and more than 150,000 people lining the streets. About 40,000 people visited his body as it lay in state in the darkened Manchester Town Hall. 

His legacy is preserved in various monuments, including a beautiful statue by Sir Francis L. Chantrey in Manchester Town Hall and a fresco by Madox Brown depicting Dalton collecting methane. His image was used on British banknotes in the late 20th century.

Dalton has been the subject of numerous books and articles, and his work is a staple of science education. There have been documentaries and historical accounts that feature his life and contributions.

ACHIEVEMENTS Formulated the modern atomic theory (1803–1808).

Introduced symbols to represent elements (September 6, 1803).

Pioneered the study of colour blindness.

Published influential works on meteorology and chemistry.

Elected a Fellow of the Royal Society in 1822.

Received honours from multiple European scientific societies.

Sources: (1) Wikisource (2) Heritage History