seamus dubhghaill

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


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Birth of Geologist Richard Dixon Oldham

richard-dixon-oldhamRichard Dixon Oldham, British geologist who makes the first clear identification of the separate arrivals of P-waves, S-waves and surface waves on seismograms and the first clear evidence that the Earth has a central core, is born in Dublin on July 31, 1858.

Born to Thomas Oldham, a Fellow of the Royal Society and a geologist, Oldham is educated at Rugby School and the Royal School of Mines.

In 1879 Oldham becomes an assistant-superintendent with the Geological Survey of India (GSI), working in the Himalayas. He writes about 40 publications for the Survey on geological subjects including hot springs, the geology of the Son Valley and the structure of the Himalayas and the Indo-Gangetic plain. His most famous work is in seismology. His report on the 1897 Assam earthquake goes far beyond reports of previous earthquakes. It includes a description of the Chedrang fault, with uplift up to 35 feet and reported accelerations of the ground that have exceeded the Earth’s gravitational acceleration. His most important contribution to seismology is the first clear identification of the separate arrivals of P-waves, S-waves and surface waves on seismograms. Since these observations agree with theory for elastic waves, they show that the Earth can be treated as elastic in studies of seismic waves.

In 1903, Oldham resigns from the GSI due to ill health and returns to the United Kingdom, living in Kew and various parts of Wales. In 1906 he writes a paper analyzing seismic arrival times of various recorded earthquakes. He concludes that the earth has a core and estimates its radius to be less than 0.4 times the radius of the Earth.

In 1908 Oldham is awarded the Lyell Medal, in 1911 made a Fellow of the Royal Society and from 1920 to 1922 serves as the President of the Geological Society of London.

Richard Dixon Oldham dies at Llandrindod Wells in Wales on July 15, 1936.

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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.


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Death of Robert Mallet, the Father of Seismology

robert-malletRobert Mallet, geophysicist, civil engineer, and inventor who distinguishes himself in research on earthquakes and is sometimes called the Father of Seismology, dies on November 5, 1881.

Mallet is born in Dublin on June 3, 1810, the son of factory owner John Mallet. He is educated at Trinity College, Dublin, entering it at the age of 16 and graduating in science and mathematics in 1830 at the age of 20.

Following his graduation, he joins his father’s iron foundry business and helps build the firm into one of the most important engineering works in Ireland, supplying ironwork for railway companies, the Fastnet Rock lighthouse, and a swing bridge over the River Shannon at Athlone. He also helps manufacture the characteristic iron railings that surround Trinity College and which bear his family name at the base.

Mallet is elected to the Royal Irish Academy in 1832 at the early age of 22. He also enrolls in the British Association for the Advancement of Science in 1835 which helps finance much of his research in seismology.

In 1838 he becomes a life member of the Royal Geological Society of Ireland, and serves as its President from 1846–1848. From 1848–1849 he constructs the Fastnet Rock lighthouse, southwest of Cape Clear.

On February 9, 1846 he presents to the Royal Irish Academy his paper On the Dynamics of Earthquakes, which is considered to be one of the foundations of modern seismology. He is also credited with coining the word “seismology” and other related words which he uses in his research. He also coins the term epicentre.

From 1852 to 1858, he is engaged in the preparation of his work, The Earthquake Catalogue of the British Association (1858), and carries out blasting experiments to determine the speed of seismic propagation in sand and solid rock.

On December 16, 1857, the area around Padula, Italy is devastated by the Great Neapolitan earthquake which causes 11,000 deaths. At the time it is the third largest known earthquake in the world and has been estimated to have been of magnitude 6.9 on the Richter Scale. Mallet, with letters of support from Charles Lyell and Charles Darwin, petitions the Royal Society of London and receives a grant of £150 to go to Padula and record at first hand the devastation. The resulting report is presented to the Royal Society as the Report on the Great Neapolitan Earthquake of 1857. It is a major scientific work and makes great use of the then new research tool of photography to record the devastation caused by the earthquake. In 1862, he publishes the Great Neapolitan Earthquake of 1857: The First Principles of Observational Seismology in two volumes. He brings forward evidence to show that the depth below the Earth’s surface, from where the impulse of the Neapolitan earthquake originated, is about 8–9 geographical miles.

One of Mallet’s papers is Volcanic Energy: an Attempt to develop its True Origin and Cosmical Relations, in which he seeks to show that volcanic heat may be attributed to the effects of crushing, contortion, and other disturbances in the crust of the earth. The disturbances leading to the formation of lines of fracture, more or less vertical, down which water would find its way, and if the temperature generated be sufficient volcanic eruptions of steam or lava would follow.

Mallet is elected Fellow of the Royal Society in 1854, and in 1861 moves to London, where he becomes a consulting engineer and edits The Practical Mechanic’s Journal. He is awarded the Telford Medal by the Institution of Civil Engineers in 1859, followed by the Cunningham Medal of the Royal Irish Academy for his research into the theory of earthquakes in 1862, and the Wollaston Medal of the Geological Society of London in 1877, the Geological Society’s highest award.

Blind for the last seven years of his life, Robert Mallet dies at Stockwell, London, on November 5, 1881 and is buried at West Norwood Cemetery.


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Birth of Richard John Griffith, Author of Griffith’s Valuation

richard-john-griffithRichard John Griffith, Irish geologist, mining engineer, and chairman of the Board of Works of Ireland, is born in Hume Street, Dublin, on September 20, 1784. He completed the first complete geological map of Ireland and is author of the valuation of Ireland, known ever since as Griffith’s Valuation.

Griffith goes to school in Portarlington and later, while attending school in Rathangan, his school is attacked by the rebels during the Irish Rebellion of 1798. He also studies in Edinburgh, Scotland.

In 1799 he obtains a commission in the Royal Irish Artillery, but a year later, when the corps is incorporated with that of England, he retires, and devotes his attention to civil engineering and mining. He studies chemistry, mineralogy, and mining for two years in London under William Nicholson and afterwards examines the mining districts in various parts of England, Wales, and Scotland.

While in Cornwall he discovers ores of nickel and cobalt in material that has been rejected as worthless. He completes his studies under Robert Jameson and others at Edinburgh, is elected a Fellow of the Royal Society of Edinburgh in 1807, a member of the newly established Geological Society of London in 1808, and in the same year he returns to Ireland.

In 1809, he is appointed by the commissioners to inquire into the nature and extent of the bogs in Ireland and the means of improving them. In 1812 he is elected Professor of Geology and Mining Engineer to the Royal Dublin Society. Shortly afterwards he expresses his intention of preparing a geological map of Ireland. During subsequent years he makes many surveys and issues many reports on mineral districts in Ireland. These form the foundation of his first geological map of the country in 1815. He also succeeds Dr. Richard Kirwan as government inspector of mines in Ireland. In 1822 Griffith becomes engineer of public works in Cork, Kerry, and Limerick, and is occupied until 1830 in repairing old roads and in laying out many miles of new roads in some of the most inaccessible parts of the country.

Meanwhile, in 1825, he is appointed by the government to carry out a boundary survey of Ireland. He is to mark the boundaries of every county, barony, civil parish, and townland in preparation for the first Ordnance Survey. He is also called upon to assist in the preparation of a parliamentary Bill to provide for the general valuation of Ireland, which passes in 1826. Griffith is appointed Commissioner of Valuation in 1827, but does not start work until 1830 when the new 6″ maps become available from the Ordnance survey and which he is required to use as provided for by statute. He continues to work on this until 1868. On Griffith’s valuation the various local and public assessments are made.

His extensive investigations furnish him with ample material for improving his geological map and the second edition is published in 1835. A third edition on a larger scale (1 in. to 4 m.) is issued under the Board of Ordnance in 1839 and it is further revised in 1855. For this great work and his other services to science Griffith is awarded the Wollaston Medal by the Geological Society in 1854. In 1850 he is made chairman of the Irish Board of Works and in 1858 he is created a baronet.

Griffith dies at the age of 95 at his residence in Dublin on September 22, 1878. At the time of his death, he is the oldest surviving fellow of the Geological Society of London and is the last survivor of the long-since disbanded Royal Irish Regiment of Artillery. He is buried alongside his wife, Maria Jane, in Mount Jerome Cemetery, Harold’s Cross, Dublin.