seamus dubhghaill

Promoting Irish Culture and History from Little Rock, Arkansas, USA

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Death of Thomas Andrews, Chemist & Physicist

thomas-andrewsThomas Andrews, chemist and physicist who does important work on phase transitions between gases and liquids, dies in Belfast on November 26, 1885. He is a longtime professor of chemistry at Queen’s University Belfast.

Andrews is born in Belfast on December 19, 1813, where his father is a linen merchant. He attends the Belfast Academy and the Royal Belfast Academical Institution, where at the latter of which he studies mathematics under James Thomson. In 1828 he goes to the University of Glasgow to study chemistry under Professor Thomas Thomson, then studies at Trinity College, Dublin, where he gains distinction in classics as well as in science. Finally, at the University of Edinburgh in 1835, he is awarded a doctorate in medicine.

Andrews begins a successful medical practice in his native Belfast in 1835, also giving instruction in chemistry at the Royal Belfast Academical Institution. In 1842, he marries Jane Hardie Walker. They have six children, including the geologist Mary Andrews.

Andrews first becomes known as a scientific investigator with his work on the heat developed in chemical actions, for which the Royal Society awards him a Royal Medal in 1844. Another important investigation, undertaken in collaboration with Peter Guthrie Tait, is devoted to ozone. In 1845 he is appointed vice-president and professor of chemistry of the newly established Queen’s University Belfast. He holds these two offices until his retirement in 1879 at the age of 66.

His reputation mainly rests on his work with liquefaction of gases. In the 1860s he carries out a very complete inquiry into the gas laws — expressing the relations of pressure, temperature, and volume in carbon dioxide. In particular, he establishes the concepts of critical temperature and critical pressure, showing that a substance passes from vapor to liquid state without any breach of continuity.

In Andrews’ experiments on phase transitions, he shows that carbon dioxide may be carried from any of the states we usually call liquid to any of those we usually call gas, without losing homogeneity. The mathematical physicist Josiah Willard Gibbs cites these results in support of the Gibbs free energy equation. They also set off a race among researchers to liquify various other gases. In 1877-78 Louis Paul Cailletet is the first to liquefy oxygen and nitrogen.

Thomas Andrews dies in Belfast on November 26, 1885 and is buried in the city’s Borough Cemetery.


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Birth of Physicist John Joly

John Joly, Irish physicist famous for his development of radiation therapy in the treatment of cancer, is born in Bracknagh, County Offaly, on November 1, 1857. He is also known for developing techniques to accurately estimate the age of a geological period, based on radioactive elements present in minerals.

Joly is a second cousin of Charles Jasper Joly, the astronomer. He enters Trinity College, Dublin in 1876, graduating in Engineering in 1882 in first place with various special certificates in branches of engineering, at the same time obtaining a First-Class Honours in modern literature. He works as a demonstrator in Trinity’s Engineering and Physics departments before succeeding William Johnson Sollas in the Chair of Geology and Mineralogy in 1897, a position which he holds until his death in 1933.

Joly joins the Royal Dublin Society in 1881 while still a student, and is a frequent contributor of papers. During his career he writes over 270 books and scientific papers.

On May 17, 1899 Joly reads his paper “An Estimate of the Geological Age of the Earth” to the Royal Dublin Society. In it, he proposes to calculate the age of the earth from the accumulation of sodium in the waters of the oceans. He calculates the rate at which the oceans should have accumulated sodium from erosion processes, and determines that the oceans are about 80 to 100 million years old. The paper is quickly published, appearing four months later in the Society’s Scientific Transactions. Although this method is later considered inaccurate and is consequently superseded, it radically modifies the results of other methods in use at the time.

In 1903 he publishes an article in Nature in which he discusses the possibility of using radium to date the Earth and goes on to study the radioactive content of the Earth’s crust to formulate a theory of thermal cycles, and examines the radioactive constituents of certain rocks as a means of calculating their age. Working in collaboration with Sir Ernest Rutherford, he uses radioactive decay in minerals to estimate, in 1913, that the beginning of the Devonian period could not be less than 400 million years ago, an estimate which is in line with modern calculations.

Joly serves as President of Section C (Geology) when the British Association for the Advancement of Science meets in Dublin in 1908, during which he presents his paper “Uranium and Geology” in an address to the society. This work describes radioactive materials in rocks and their part in the generation of the Earth’s internal heat.

Along with his friend Henry Horatio Dixon, Joly also puts forward the cohesion-tension theory which is now thought to be the main mechanism for the upward movement of water in plants.

In 1914 Joly develops a method of extracting radium and applies it in the treatment of cancer. As a Governor of Dr. Steevens’ Hospital in Dublin, in collaboration with Walter Stevenson, he devises radiation therapy methods and promotes the establishment by the Royal Dublin Society of the Irish Radium Institute where they pioneer the “Dublin method” of using a hollow needle for deep radiation therapy, a technique that later enters worldwide use. The Radium Institute also supplies capillary tubes containing radon to hospitals for some years for use in the treatment of tumours.

Joly is elected a Fellow of the Royal Society of London in 1892, is awarded the Boyle Medal of the Royal Dublin Society in 1911, the Royal Medal of the Royal Society of London in 1910, and the Murchison Medal of the Geological Society of London in 1923. He is also conferred honorary degrees by the National University of Ireland, the University of Cambridge, and the University of Michigan. After his death in 1933, his friends subscribe the sum of £1,700 to set up a memorial fund which is still used to promote the annual Joly Memorial Lectures at the University of Dublin, which were inaugurated by Sir Ernest Rutherford in 1935. He is also remembered by the Joly Geological Society, a student geological association established in 1960.

In 1973 a crater on Mars is named in Joly’s honour.