John Dalton

In honour of his work with ratios and chemicals that led to the idea of atoms and atomic weights, many chemists and biochemists use the (still unofficial) unit dalton (abbreviated Da) to denote one atomic mass unit, or 1/12 the weight of a neutral atom of carbon-12. It has not been ruled out that the bodies were cadavers when Franklin got them; Franklin had an avid interest in anatomy and the damages done to the bodies support that. However, an eye was preserved at the Royal Institution, and a 1990s study on DNA extracted from the eye showed that he had lacked the pigment that gives sensitivity to the colour green, the classic condition known as a deuteranope. The Times of London reported on February 11, 1998:. Post-mortem examination showed that the humours of the eye were perfectly normal. In 1998, workmen restoring Franklin's London home dug up the remains of six children and four adults hidden below the home. He had hypothesised that his aqueous humour might be coloured blue. It is one of the few National Memorials located on private property.

Dalton had requested that his eyes be examined after his death, in an attempt to discover the cause of his colour-blindness. The memorial is located in Philadelphia's Franklin Institute. It now stands in the entrance to Manchester Town Hall. Many of Franklin's personal possessions are also on display there. A bust of him, by Francis Legatt Chantrey, was publicly subscribed for him and placed in the entrance hall of the Royal Manchester Institution. In 1976, as part of a bicentennial celebration, Congress dedicated the Benjamin Franklin National Memorial in Franklin's hometown of Philadelphia, including a 20-foot high marble statue. On the 27th he fell from his bed and was found lifeless by his attendant. Franklin also appears on the $1,000 Series EE Savings Bond (See Treasury security).

In May 1844 he had another stroke and on July 26 he recorded with trembling hand his last meteorological observation. He has also appeared on a $50 bill in the past, as well as several varieties of the $100 bill from 1914 and 1918, and every $100 bill from 1928 to present. He had suffered a first attack in 1837, and a second in 1838 had left him enfeebled, both physically and mentally, though he remained able to make experiments. As a result, $100 bills are sometimes referred to in slang as "Benjamins" or "Franklins." From 1948 to 1964, Franklin's portrait was also on the half dollar. Dalton died in Manchester in 1844 of paralysis. Franklin's likeness adorns the American $100 bill. He attended several of the earlier meetings of the British Association at York, Oxford, Dublin and Bristol. In recent years a number of anti-Semitic groups have been promoting a fabricated quotation which has been debunked by historians: Neo-Nazi Theory (American founding fathers).

In 1822 he paid a short visit to Paris, where he met many distinguished resident scientists. (excerpt from Philadelphia Inquirer article by Clark De Leon). Johns (1771–1845), in George Street, Manchester, where his daily round of laboratory work and tuition was broken only by annual excursions to the Lake District and occasional visits to London. Franklin's Boston trust fund accumulated almost $5,000,000 during that same time and eventually was used to establish a trade school that, over time, became the Franklin Institute of Boston. W. When the trust came due, Philadelphia decided to spend it on scholarships for local high school students. He lived for more than a quarter of a century with his friend the Rev. From 1940 to 1990, the money was used mostly for mortgage loans.

Dalton never married, though there is evidence that he enjoyed the company of educated and refined women. During the lifetime of the trust, Philadelphia used it for a variety of loan programs to local residents. In 1833 Lord Grey's government conferred on him a pension of £150, raised in 1836 to £300. As of 1990 over $2,000,000 had accumulated in Franklin's Philadelphia trust since his death. Six years previously he had been made a corresponding member of the French Académie des Sciences, and in 1830 he was elected as one of its eight foreign associates in place of Davy. Franklin, who was 79 years old at the time, wrote back to the Frenchman, thanking him for a great idea and telling him that he had decided to leave a bequest to his native Boston and his adopted Philadelphia of 1,000 pounds to each on the condition that it be placed in a fund that would gather interest over a period of 200 years. However, in 1822 he was proposed without his knowledge, and on election paid the usual fee. The Frenchman wrote a piece about Fortunate Richard leaving a small sum of money in his will to be used only after it had collected interest for 500 years.

In 1810 he was asked by Davy to offer himself as a candidate for the fellowship of the Royal Society, but declined, possibly for financial reasons. In it he mocked the unbearable spirit of American optimism represented by Franklin. However, he was deficient, it would seem, in the qualities that make an attractive lecturer, being harsh and indistinct in voice, ineffective in the treatment of his subject, and singularly wanting in the language and power of illustration. The origin of the trust began in 1785 when a French mathematician named Charles-Joseph Mathon de la Cour wrote a parody of Franklin's Poor Richard's Almanack called Fortunate Richard. In 1804 he was chosen to give a course of lectures on natural philosophy at the Royal Institution in London, where he delivered another course in 1809–1810. At his death Franklin bequeathed £1000 (about $4400 at the time) each to the cities of Boston and Philadelphia, in trust for 200 years. Before he had propounded the atomic theory he had already attained a considerable scientific reputation. Benjamin Franklin died on April 17, 1790 at the extremely advanced age (for that time) of 84, and was interred in Christ Church Burial Ground in Philadelphia, Pennsylvania.

His library, he was once heard to declare, he could carry on his back, yet reputedly he had not read half the books it contained. Because of his involvement in abolition, its cause was greatly debated around the states, especially in the House of Representatives. He always objected to the chemical notation devised by Jöns Jakob Berzelius, although by common consent it was much simpler and more convenient than his own cumbersome system of circular symbols. Their argument against slavery was backed by the Pensylvania Abolitionist Society and its president, Benjamin Franklin. Even after its elementary character had been settled by Davy, he persisted in using the atomic weights he himself had adopted, even when they had been superseded by the more accurate determinations of other chemists. On February 11, 1790, Quakers from New York and Pennsylvania presented their petition for abolition. He held peculiar and quite unfounded views about chlorine. These writings included:.

Thus he distrusted, and probably never fully accepted, Gay-Lussac's conclusions as to the combining volumes of gases. In his later years, as congress was forced to deal with the issue of slavery, Franklin wrote several essays that attempted to convince his readers of the importance of the abolition of slavery and of the integration of Africans into American society. of his New System he says he had so often been misled by taking for granted the results of others that he determined to write as little as possible but what I can attest by my own experience, but this independence he carried so far that it sometimes resembled lack of receptivity. Later, he finished his autobiography between 1771 and 1788, at first addressed to his son, then later completed for the benefit of mankind at the request of a friend. i. It is now called Franklin and Marshall College. In the preface to the second part of vol. Franklin donated £200 towards the development of Franklin College, which would later merge with Marshall College in 1853.

Sir Humphry Davy described him as a very coarse experimenter, who almost always found the results he required, trusting to his head rather than his hands. Also in 1787, a group of prominent ministers in Lancaster, Pennsylvania proposed the foundation of a new college to be named in Franklin's honor. As an investigator, Dalton was content with rough and inaccurate instruments, though better ones were readily attainable. He was 70 years old when he signed the Declaration, and 81 when he signed the Constitution. He took the same course soon afterwards with four other papers, two of which On the quantity of acids, bases and salts in different varieties of salts and On a new and easy method of analysing sugar, contain his discovery, regarded by him as second in importance only to the atomic theory, that certain anhydrates, when dissolved in water, cause no increase in its volume, his inference being that the salt enters into the pores of the water. Franklin also has the distinction of being the oldest signer of both the Declaration of Independence and the United States Constitution. In 1840 a paper on the phosphates and arsenates, often regarded as a weaker work, was refused by the Royal Society, and he was so incensed that he published it himself. He is the only Founding Father who is a signatory of all three of the major documents of the founding of the United States: The Declaration of Independence, The Treaty of Paris and the United States Constitution.

In one of them, read in 1814, he explains the principles of volumetric analysis, in which he was one of the earliest workers. While in retirement by 1787, he agreed to attend as a delegate the meetings that would produce the United States Constitution to replace the Articles of Confederation. Of these the earlier are the most important. In addition, after his return from France in 1785, he became a slavery abolitionist who eventually became president of The Society for the Relief of Free Negroes Unlawfully Held in Bondage. Dalton was president of the Lit & Phil from 1817 until his death, contributing 116 memoirs. When Franklin was recalled to America in 1785, Le Ray honored him with a commissioned portrait painted by Joseph Siffred Duplessis that now hangs in the National Portrait Gallery of the Smithsonian Institution in Washington, DC. never appeared. He conducted the affairs of his country towards that nation with such success, which included securing a critical military alliance and negotiating the Treaty of Paris (1783), that when he finally returned, he received a place only second to that of George Washington as the champion of American independence.

ii. Franklin was so popular that it became fashionable for wealthy French families to decorate their parlors with a painting of him. The second part of vol. Ben Franklin remained in France until 1785, a favorite of French society. This delay is not explained by any excess of care in preparation, for much of the matter was out of date and the appendix giving the author's latest views is the only portion of special interest. He lived in a home in the Parisian suburb of Passy donated by Jacques-Donatien Le Ray de Chaumont who would become a friend and the most important foreigner to help the United States win the war of independence. The second part of this volume appeared in 1810, but the first part of the second volume was not issued till 1827, though the printing of it began in 1817. In December of 1776 he was dispatched to France as commissioner for the United States.

Dalton communicated his atomic theory to Thomson who, by consent, included an outline of it in the third edition of his System of Chemistry (1807), and Dalton gave a further account of it in the first part of the first volume of his New System of Chemical Philosophy (1808). On his arrival in Philadelphia he was chosen as a member of the Continental Congress and assisted in editing the Declaration of Independence. However, he was the first to put the ideas into a universal atomic theory, which was undoubtedly his greatest achievement. In 1767 he crossed to France, where he was received with honor; but before his return home in 1775 he lost his position as postmaster through his share in divulging to Massachusetts the famous letter of Hutchinson and Oliver. Many of Dalton's ideas were acquired from other chemists at the time, such as Antoine Lavoisier and William Higgins. This also led to an irreconcilable conflict with his son, who remained ardently loyal to the British Government. It may be noted that in a paper on the proportion of the gases or elastic fluids constituting the atmosphere, read by him in November 1802, the law of multiple proportions appears to be anticipated in the words: The elements of oxygen may combine with a certain portion of nitrous gas or with twice that portion, but with no intermediate quantity, but there is reason to suspect that this sentence was added some time after the reading of the paper, which was not published till 1805. Even his effective work in helping to obtain the repeal of the act did not regain his popularity, but he continued his efforts to present the case for the Colonies as the troubles thickened toward the crisis of the Revolution.

The extension of this idea to substances in general necessarily led him to the law of multiple proportions, and the comparison with experiment brilliantly confirmed his deduction^[3]. This perceived conflict of interest, and the resulting outcry, is widely regarded as a deciding factor in Franklin's never achieving higher elected office. Assisted by the assumption that combination always takes place in the simplest possible way, he thus arrived at the idea that chemical combination takes place between particles of different weights, and this it was which differentiated his theory from the historic speculations of the Greeks. In London he actively opposed the proposed Stamp Act, but lost the credit for this and much of his popularity because he secured for a friend the office of stamp agent in America. It appears, then, that confronted with the problem of calculating the relative diameter of the atoms of which, he was convinced, all gases were made, he used the results of chemical analysis. On his return to America, he played an honorable part in the Paxton affair, through which he lost his seat in the Assembly, but in 1764 he was again dispatched to England as agent for the colony, this time to petition the King to resume the government from the hands of the proprietors. by chemists of the time. In his letter “Cooling by Evaporation” Franklin noted that “one may see the possibility of freezing a man to death on a warm summer’s day.”.

He proceeds to give what has been quoted as his first table of atomic weights, but in his laboratory notebooks^[2] there is an earlier one dated 1803 in which he sets out the relative weights of the atoms of a number of substances, derived from analysis of water, ammonia, carbon dioxide, etc. Another thermometer showed the room temperature to be constant at 65 °F (18 °C). Here he says:. With each subsequent evaporation, the thermometer read a lower temperature, eventually reaching 7 °F (-14 °C). The first published indications of this idea are to be found at the end of his paper on the absorption of gases already mentioned, which was read on October 21, 1803 though not published till 1805. On one warm day in Cambridge England in 1758, Franklin and fellow scientist John Hadley experimented by continually wetting the ball of a mercury thermometer with ether and using bellows to evaporate the ether. However, a study of Dalton's own laboratory notebooks, discovered in the rooms of the Lit & Phil^[1], concluded that so far from Dalton being led to the idea, that chemical combination consists in the interaction of atoms of definite and characteristic weight, by his search for an explanation of the law of multiple proportions, the idea of atomic structure arose in his mind as a purely physical concept, forced upon him by study of the physical properties of the atmosphere and other gases. To understand this phenomenon more clearly Franklin conducted experiments.

It has been proposed that this theory was suggested to him either by researches on ethylene (olefiant gas) and methane (carburetted hydrogen) or by analysis of nitrous oxide (protoxide of azote) and nitrogen dioxide (deutoxide of azote), both views resting on the authority of Thomas Thomson. Franklin noted a principle of refrigeration by observing that on a very hot day, he stayed cooler in a wet shirt in a breeze than he did in a dry one. The most important of all Dalton's investigations are those concerned with the atomic theory in chemistry, with which his name is inseparably associated. In 1758, the year in which he ceased writing for the Almanac, he printed "Father Abraham's Sermon," one of the most famous pieces of literature produced in Colonial America. In the two or three years following the reading of these essays, he published several papers on similar topics, that on the absorption of gases by water and other liquids (1803), containing his law of partial pressures. At Oxford University Franklin was awarded an honorary doctorate for his scientific accomplishments and from then on went by "Doctor Franklin." He also managed to secure a post for his illegitimate son, William Franklin, as Colonial Governor of New Jersey. He thus enunciated Gay-Lussac's law, stated some months later by Joseph Louis Gay-Lussac. In 1757 he was sent to England to protest against the influence of the Penn family in the government of Pennsylvania, and for five years he remained there, striving to enlighten the people and the ministry of the United Kingdom as to colonial conditions.

In the fourth essay he remarks,. While the plan was not adopted, elements of it found their way into the Articles of Confederation and the Constitution. After describing experiments to ascertain the pressure of steam at various points between 0 ° and 100°C (32° and 212°F), he concluded from observations on the vapour pressure of six different liquids, that the variation of vapour pressure for all liquids is equivalent, for the same variation of temperature, reckoning from vapour of any given pressure. Franklin proposed a broad Plan of Union for the colonies. The second of these essays opens with the striking remark,. This meeting of several colonies had been requested by the Board of Trade in England to improve relations with the Indians and defense against the French. In 1800 he became a secretary of the Lit & Phil, and in the following year he presented the important paper or series of papers, entitled Experimental Essays on the constitution of mixed gases; on the pressure of steam and other vapours at different temperatures, both in a vacuum and in air; on evaporation; and on the thermal expansion of gases. In 1754 he headed the Pennsylvania delegation to the Albany Congress.

This paper was followed by many others on diverse topics on rain and dew and the origin of springs, on heat, the colour of the sky, steam, the auxiliary verbs and participles of the English language and the reflection and refraction of light. It was during this period that Franklin was involved in the creation of not only the aforementioned first volunteer fire department and free public library, but also many other civic enterprises. After that the orange, yellow and green seem one colour which descends pretty uniformly from an intense to a rare yellow, making what I should call different shades of yellow. His most notable service in domestic politics was his reform of the postal system, but his fame as a statesman rests chiefly on his diplomatic services in connection with the relations of the colonies with Great Britain, and later with France. Besides the blue and purple of the spectrum he was able to recognize only one colour, yellow, or, as he says in his paper, that part of the image which others call red appears to me little more than a shade or defect of light. In politics he proved very able both as an administrator and as a controversialist; as an office-holder, he made use of his position to advance his relatives, though doing so was all but expected in a world dominated by political patronage. In 1794 he was elected a member of the Manchester Literary and Philosophical Society, the Lit & Phil, and a few weeks after election he communicated his first paper on Extraordinary facts relating to the vision of colours, in which he gave the earliest account of the optical peculiarity known as Daltonism or colour blindness, and summed up its characteristics as observed in himself and others, including his brother. Pennsylvania Hospital was the first hospital in what was to become the United States of America.