Of Protestant ascendancy, the name JOLY became established in the midlands of Ireland in Co.Offaly, of which the principal town is Tullamore. Historically known as King’s County, the achievements of the second distinguished family from Offaly in scientific invention and progress have brought fame to Ireland and beyond.
Well known for his scientific and other inventions, John Joly was described as … a remarkable man. He was popular, well loved and respected. His private interests were many and he travelled widely especially to the European Alps which he enjoyed climbing. He never married and died in Dublin in 1933.
John Joly (1857-1933)
John Joly was born at the Rectory of Holywood House, Bracknagh in King’s County (now Co. Offaly) Ireland. He was the third son of the Rev. John Plunkett Joly M.A., of Clonbullogue, Co. Offaly, and of Julia Anna Maria Georgina n ?e Comtesse de Lusi of aristocratic descent. Both parents had remarkable ancestry.
His father’s family was originally French. As early as 1420 Reginald Joly of this family was “Conseilleur”. Of the same family Georges was appointed to the King’s “Conseil” in 1621 and became its president in 1644. He died in 1679. John Joly’s mother was the daughter of Friedrich Wilhelm Ludwig August Graf von Lusi and Maria, daughter of Sir Duke Giffard.
Ireland and beyond
John Joly was educated privately, then at Trinity College Dublin (TCD) from 1876 graduating in Engineering and Literature in 1882. He worked in Engineering and Physics becoming professor of Geology and Mineralogy at TCD, a post he held from 1897 to 1933, partly in recognition of his various inventions.
These feature in particular a photometer for measuring light intensity or illumination, a meldometer for measuring the melting points of minerals, a differential steam calorimeter for measuring specific heats and a constant-volume gas thermometer, all of which bear his name, together with other lesser-known contrivances, such as a radio method of signalling at sea.
In the 1890s he developed a process for colour photography, commercialised as the Joly Process, and went to the United States to defend his patents against Kodak. He was a pioneer and enthusiast of motion pictures, making and showing them in TCD. His geological work was mainly in geochronology. In 1894 he invented the method of “photography in natural colours” and for the first time made possible the easy production of accurately coloured transparent pictures. A large collection of colour slides by John Joly mainly of botanical subjects are held by the National Library of Ireland.
Working with Sir Ernest Rutherford in Cambridge, one of his claims to international fame was the making of an accurate estimate of the age of a geological period - an essential step in estimating the age of the earth. In 1898 he estimated the age of the earth based on the astronomer and mathematician Edmond Halley’s method of measuring the salinity of the sea, as 80-90 million years (later revised to 100 million years). It radically modified the results of other methods including one by a previous Trinity academic and ecclesiast who used the bible for the same purpose. The Joly Memorial Lectures were inaugurated in 1935 by Sir Ernest Rutherford and still continue.
He collaborated with his close friend, Henry Horatio Dixon (1869-1953) who was Professor of Botany at Trinity College for many years, in explaining how sap rises in plants, the first time this had been done. With the discoveries and inventions to his name, including his method for colour photography that he patented, John Joly was elected a Fellow of the Royal Dublin Society in 1892 for work on the specific heat of gases at constant level. He was a prolific writer and eventually his published papers numbered 270. His books include the seminal Radioactivity and Geology (1909) and the influential Surface History of the Earth (1925).
A staunch unionist, in his younger days he defended Trinity College during the Easter Rising in Dublin (24 April – l May 1916), a pivotal event in Ireland’s historical struggle for independence. He is said to have ventured forth from the defences of Trinity College in search of fresh intelligence and cigarettes for his comrades to where he returned safely.
As a Governor, in collaboration with Walter Stevenson of Dr. Steevens’ Hospital, Dublin, he devised new methods of radiotherapy and actively promoted establishment by the Royal Dublin Society of the Irish Radium Institute where they pioneered the ‘Dublin method’ of using a hollow needle for use in deep-seated radiotherapy, a technique that was to come into worldwide use. He won the Boyle Medal of the Royal Dublin Society in 1911 and the Murchison Medal of the Geological Society of London in 1923. He was elected a Fellow of Trinity College Dublin (TCD) in 1919 and received honorary degrees in the United States and Russia.
A photograph in profile shows an elegant image of John Joly bespectacled with white hair and a heavy moustache that helps to personify the man and his great achievements. As one of Ireland’s most fertile scientific minds he spent all his working life in Trinity.
Eminent Joly family
Aged 76, John Joly died in Dublin on 8 December 1933. His obituary was published in JSTOR Obituary Notices of Fellows of the Royal Society, Vol. 1, No. 3 (Dec.1934), pp. 259-286. Forty years after his death he was honoured when a crater on Mars was named after him.
The family graveyard at St. Kevin’s Church, Clonbullogue, Co.Offaly, has marble plaques and a memorial stained glass window to the eminent Joly family in Ireland about whom the author has written separate texts.
Ita Marguet, June 2008
Note : Acknowledgement is given to all sources used in preparation of this text. It follows published texts The name Joly : Celebration and dedication (Dec. 2004) and Heritage of Ireland : JOLY Collection revisited (Dec. 2006) by Ita Marguet.
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