John Dalton
1766-1844

The Colour-Blind Chemist who Gave us Our Chemical Atoms

John Dalton was born in a little village near Cockermouth, in Cumberland, the date of his birth being 1766, or approximately one hundred and fifty years ago, and in the reign of George III. Our hero was born in a thatched cottage in which his father earned a living as a handloom weaver. Both his parents came of families belonging to the Society of Friends, and their boy naturally became a Quaker also.

As a schoolboy John was not brilliant, but he was persistently persevering. This trait of his character became very noticeable when a rich Quaker friend undertook to give Dalton, and a young man twice his age, special lessons in arithmetic. When a difficult problem was set for these two young friends, the older one was very willing, after a first vain attempt at its solution, to ask for an explanation, whereas John Dalton pleaded for more time, determined to master it for himself. Sometimes he would even ask if he might keep the problem over-night, so that he might try and work it out in the morning, which he often succeeded in doing.

When Dalton was twelve years of age he nailed up a large sheet of paper, on the front of his father's cottage, announcing that John Dalton had opened a school for both sexes on reasonable terms, and that paper, pens, and ink could be bought within. This boy-schoolmaster had a number of pupils ranging from infants to boys and girls of seventeen. With the bigger boys he must have been at a decided disadvantage when there was any occasion for punishment. This original style of school was carried on for two years, but as it became apparent that John would never make a fortune out of his reasonable terms, it was decided that he should turn farmer. This may have been suggested by the fact that John had an uncle who was a farmer and who had no sons to follow him in possession of the farm. John was set to learn ploughing on a patch of land which his father, the weaver, farmed on his own account.

In the evenings, so soon as outdoor work was over, John sat down to study, and to some purpose, for by the time he was fifteen he was appointed an assistant in a Quaker school at Kendal, in which his older brother was already a teacher. The distance from Dalton's home to this town amidst the English Lakes was forty miles, but there was no regular conveyance, so the lad of fifteen set out to cover the distance on foot, carrying his belongings in a cloth bundle, and armed with a large umbrella, which he thought would be fitting to his new post.

After a few years the proprietor of the school retired, and the two Daltons carried it on with some success on their own account. The financial success was not great; the total income for any one year did not exceed one hundred pounds. The terms that the former proprietor had charged for scholars boarding in the school were ten shillings and sixpence per quarter, and when the Daltons announced an increase of the charge to fifteen shillings they stated that they hoped the terms would not be thought unreasonable, as there had been an increase in the cost of food materials.

John still gave all his spare time to study, and he seems to have been taken up with mathematics, for one of the pupils, in describing the school, has stated that the boys preferred John as their teacher, not only because he was less rough, but because his mind was so taken up with mathematical problems that the boys' mistakes would pass unnoticed. This is so like many schoolboys of to-day, quite pleased to get through with their lessons anyhow, with no real concern as to the acquisition of knowledge, or the training of their minds.

After twelve years' residence in Kendal, John Dalton, then twenty-seven years of age, received the appointment of tutor of Mathematics and Natural Philosophy in the New College, Manchester. This college was practically a continuation of the Warrington Academy in which one of our heroes, the Rev. Dr. Joseph Priestley, had been a lecturer (page 169). The college was a practical protest against the large Universities excluding Unitarians and Quakers, which even Oxford and Cambridge did in these days.

Dalton seems to have been about thirty years of age before he took any definite interest in chemistry; indeed, it is a wonder that he found time even then, as his tutorial duties employed him during most of the day and evening. He retired from the college after six years, so that he might devote more time to chemistry. He opened a small laboratory in the neighbourhood of his lodgings, but he had to make his living as a private tutor.

Dalton soon made a name for himself as a chemist, and when he announced his theory of chemical atoms he became famous at home and abroad. Long afterwards a learned French chemist came over from Paris in order that he might see the great English chemist. He thought all he would have to do would be to come to Manchester, and there find Dalton in some great College or University, but instead of that he had to search for his lodgings in a clergyman's humble home in a back street. Dalton was then sixty years of age, and when the French savant was ushered into the room, he found the old gentleman peering over a boy's shoulder at some figures on a slate. The distinguished Frenchman thought there was some misunderstanding, but when he asked if he had the honour of addressing Monsieur Dalton, that worthy gentleman replied, "Yes! Wilt thou sit down whilst I put this lad right about his arithmetic?" Right throughout life Dalton had to support himself by teaching, until he was sixty-seven years of age, when the Government granted him a pension in token of his great work. It was a pity that this great man had to spend so much valuable time in ordinary school-teaching.

After Dalton had become famous he was invited to lecture in the Royal Institution in London. This was when Humphry Davy was a young assistant in the institution, he being a dozen years younger than Dalton. In a letter from John Dalton to his brother he tells that Humphry Davy has rooms next to his in the Institution, and his description of Davy is: "He is a very agreeable and intelligent young man, and we have interesting conversations in an evening. The principal failing in his character is that he does not smoke." Then Dalton proceeds to tell how Davy took him into the Lecture Theatre and made him go through his first lecture. Davy first of all acted as audience, and then he made Dalton the audience while he read the lecture, and together they criticised it.

Dalton's impression of London is given in another letter, and he was of much the same opinion as the young curate in The Private Secretary, who kept saying, "I don't like London." Dalton says: "London is a most surprising place, worth one's while to see once; but the most disagreeable place on earth for one of a contemplative turn to reside in constantly." His words remind one of the Japanese proverb: "He who has never climbed Fujiamha is a fool; but he who has climbed it more than once is a greater fool."

A Famous Lecture Theatre This picture shows the Lecture Theatre of the Royal Institution (London). Many of our heroes of Science lectured here, including Davy, Dalton, Faraday, Tyndall and Huxley. In the picture Faraday is seen delivering a lecture before a distinguished audience.

Dalton's impression of Edinburgh is very different: "It is worth while coming an hundred miles merely to see Edinburgh. It is the most romantic place and situation I ever saw; the houses touch the clouds. In this place they do not build houses side by side as with you; they build them one upon another. My own lodgings are up four flights of stairs from the front street, and five from the back. I have just one hundred steps to descend before I reach the real earth. To look down from my windows into the street at first made me shudder, but I am now got so familiar with the view that I can throw up the window and rest on the wall, taking care to keep one foot as far back in the room as I can to guard the centre of gravity."

Dalton never married. He lived for thirty years in the humble home of his friend, the Rev. William Johns, of Manchester. It is interesting to note how a chance observation led to so long a residence and lifelong friendship. The facts have been related by the clergyman's daughter: "As my mother was standing at her parlour window, one evening towards dusk, she saw Dr. Dalton passing on the other side of the street, and, on her opening the window, he crossed over and greeted her. 'Mr. Dalton,' said she, 'how is it that you so seldom come to see us?' 'Why, I don't know,' said he, 'but I have a mind to come and live with you.' My mother thought at first that he was in jest; but finding that he really meant what he said, she asked him to call again the next day, after she should have consulted my father. Accordingly he came and took possession of the only bedroom at liberty, which he continued to occupy for nearly thirty years. And here I may mention, to the honour of both, that throughout that long connection he and my father never on one occasion exchanged one angry word, and never ceased to feel for each other those sentiments of friendly interest which, on the decline into years of both, ripened into still warmer feelings of respect and affection."

Miss Johns gives also a description of Dalton's daily life. He spent practically the whole day in his laboratory, coming over for dinner, but always when it was nearly finished, which practice was doubtless to save spending too much time at meals. He would go over to his laboratory before breakfast and light the fire, and but for his meals he remained in the laboratory till nine o'clock in the evening. After supper they would all sit round the fire for a little while the clergyman and the chemist smoked their long pipes, but after that Dalton would study till midnight.

Although Dalton never married, he was by no means a woman-hater. In a letter to Mrs. Johns, writing from London, he says that he might have described the fashionable dresses of the ladies, but that he was too much taken up admiring their pretty faces. And in a letter to his brother, written on another occasion altogether, he acknowledges having fallen in love with a widow, upon whom he had called in connection with her son's studies at the Manchester College: "During my captivity, which lasted about a week, I lost my appetite, and had other symptoms of bondage about me, as incoherent discourse, etc., but have now happily regained my freedom."

In another confidential letter to his brother he goes into raptures over the charms of another young lady. Dalton used to say that he had had no time to marry, but there seems little doubt that it was because he could not well afford to set up house.

The name of our hero is prominent in connection with the subject of colour-blindness, which defect was known at one time as Daltonism. There is a story told of Dalton, while schoolmaster at Kendal, making the purchase of a pair of stockings as a present for his mother. Seeing the stockings in a shop-window labelled "Silk and Newest Fashion," he went in and bought a pair, thinking they would be something out of the ordinary for his mother, who, would doubtless wear home-knit hose of a heavier kind. The presentation pair of stockings proved to be more uncommon than John had anticipated. When his mother opened the parcel she said: "Thou hast bought me a pair of fine hose, John, but what made thee fancy such a bright colour? Why, I can never show myself at meeting in them." John thought there was something wrong with his mother's eyesight, as the stockings appeared to him to be of a dark bluish drab colour. When he expressed his surprise to his mother she exclaimed: "Why, they're as red as a cherry, John." But John called his brother Jonathan to decide the disputed point, and the latter agreed with his brother that their mother's vision was seriously at fault. She, not being satisfied with this double judgment, took the stockings to her neighbours, and came back with the general verdict, "Varra fine stuff, but uncommon scarlety."

The foregoing story is interesting, and I have no doubt is substantially correct, but it is stated as "the first event which opened John Dalton's eyes to the fact that his and his brother's vision was not as other men's." But this is evidently not so, for I find that in a paper which Dalton read to the Philosophical Society of Manchester, in 1794, he says: "I was never convinced of a peculiarity in my vision till I accidentally observed the colour of the flower Geranium zonate by candlelight in the autumn of 1792." From the date of this discovery we find that he was still at Kendal, which he left during the following year, so that the incident of the stockings was evidently prior to the discovery by candlelight. Contrary to the generally accepted idea, I can quite understand that the stocking incident did not convince Dalton that there was any peculiarity in his vision, he would think that it was merely the description of the colour that was at fault. Perhaps my point will be made clear by the following incident.

On one occasion when I was reading a paper relating to colour-blindness to a learned Society, an eminent Professor of Medicine asked me if I could explain a case which had come under his notice, in which he found a very intelligent gentleman of seventy years of age who had come through life quite ignorant of the fact that he was colour-blind. In reply I quoted a passage from Dalton's original paper, which I think makes the matter quite clear: "I was always of opinion, though I might not often mention it, that several colours were injudiciously named." And again: "When I used to call pink sky-blue and incur the ridicule of others, I used to join in the laugh myself, and then nobody thought I was in earnest; nor did I think at that time that there was such a great difference in the appearance of colour to me and others as there now seems there is. I thought we differed chiefly in words, and not ideas."

In one of Dalton's letters he tells how he had been at the house of a friend who was a dyer, when, besides his friend and himself, there were present the dyer's wife, a physician, and a young lady friend. The question of colour-vision was evidently raised, for the dyer's wife; brought in a piece of cloth to see how Dalton would describe it. He said that the last time he called upon them he was wearing a suit just of that colour, and that he should describe it as a reddish snuff-colour. This was quite a good joke to the rest of the party, as the cloth was of a grass-green colour, and certainly not the sort of colour that Quaker Dalton would wear. They told him he would not be allowed into the Meeting-house in such a green coat.

When Dalton was preparing to visit the French savants in Paris, he visited his tailor in Manchester, and ordered a suit of clothes to be made for the occasion. He took a look round among the pieces of different cloths and settled his choice upon one which he considered appropriate. Had his tailor fulfilled the order, the devout Quaker would have appeared among the learned men of France dressed in a complete suit of bright scarlet. However, the tailor, who was evidently aware of Dalton's so-called "Daltonism," pointed out to his client that this particular material was used only for making hunting coats. Dalton was so frank about his defective colour-vision that he must have received much good-humoured chaff on the subject. For instance, in reply to a letter written by Dalton, in which he had made inquiries concerning the colour-vision of a family, the following remark is made concerning our hero: "I find by your accounts you must have very imperfect ideas of the charms which in a great measure constitute beauty in the female sex: I mean that rosy blush of the cheeks which you so much admire for being light blue, I think a complexion nearly as exceptional in the fair sex as the sunburnt Moor's or the sable Ethiopian's, consequently (if real) a fitter object for a show than for a wife."

Dalton read more than one hundred scientific papers to the Literary and Philosophical Society of Manchester, of which he was President for many years. He used to make quaint remarks from the President's chair, being very fond of a sly joke. For instance, on one occasion when some one was reading a paper which was stupid and meaningless and was quite apparently a waste of the Society's time, Dalton remarked in a very audible whisper to the Secretaries who sat near him, "Well, this is a very interesting paper for those that take any interest in it."

Dalton was a great walker, proof of which we had in his forty-mile walk from his home to Kendal, a journey which he repeated often, preferring to walk at least a good bit of the way. While in Manchester he was still fond of country walks. The only other recreation he had was a game of bowls with some friends every Thursday afternoon at the "Dog and Partridge," some three miles distant from the centre of Manchester. But despite all his incessant toil and hurrying of meals, Dalton kept good health, until he had a slight paralytic stroke at the age of seventy-one. However, he recovered very quickly, and although he had a second slight stroke the following year, he lived on and was able to go about for another seven years. Indeed, he was going about as usual up to the very last, but on coming in one evening his servant noticed that his hand trembled, more than he had ever seen it before, when making an entry in his meteorological book. He passed away the following morning, "imperceptibly as an infant sinking into sleep."

And so the old Quaker of seventy-eight years was laid to rest. The people of Manchester asked that the funeral might be a public one, and we have evidence of the high esteem in which Dalton was held in the fact that no less than forty thousand people visited the darkened Town Hall where his remains were placed prior to the funeral. His life-long friend, Miss Johns, said, "His reverence for the great Author of all things was deep and sincere, as also for the Scriptures."