George FitzGerald was a brilliant mathematical physicist who today is known by most scientists as one of the proposers of the FitzGerald-Lorentz contraction in the theory of relativity. However, this suggestion by FitzGerald, as we shall see below, was not in the area in which he undertook most of his research, and he would certainly not have rated this his greatest contribution.
George FitzGerald's parents were William FitzGerald and Anne Frances Stoney. His father William was a minister in the Irish Protestant Church and rector of St Ann's Dublin at the time of George's birth. William, although having no scientific interests himself, was an intellectual who went on to become Bishop of Cork and later Bishop of Killaloe. It seems that George's later interest in metaphysics came from his father's side of the family. George's mother was the daughter of George Stoney from Birr in King's County and she was also from an intellectual family. George Johnstone Stoney, who was Anne's brother, was elected a Fellow of the Royal Society of London and George FitzGerald's liking for mathematics and physics seems to have come mainly from his mother's side of the family.
William and Anne had three sons, George being the middle of the three. Maurice FitzGerald, one of George's two brothers, also went on to achieve academic success in the sciences, becoming Professor of Engineering at Queen's College Belfast. George's schooling was at home where, together with his brothers and sisters, he was tutored by M A Boole, who was George Boole's sister. It is doubtful whether Miss Boole realised what enormous potential her pupil George had, for although he showed himself to be an excellent student of arithmetic and algebra, he was no better than an average pupil at languages and had rather a poor verbal memory. However, when the tutoring progressed to a study of Euclid's Elements then George showed himself very able indeed, and he also exhibited a great inventiveness for mechanical constructions, having great dexterity. He was also an athletic boy yet he had no great liking for games.
Miss Boole prepared her pupils very well for their university studies. She noticed one remarkable talent in her pupil George, that was his skill as an observer. Many years later FitzGerald, clearly thinking of his own youth, wrote:-
The cultivation and training of the practical ability to do things and to learn from observation, experiment and measurement, is a part of education which the clergyman and the lawyer can maybe neglect, because they have to deal with emotions and words, but which the doctor and the engineer can only neglect at their own peril and that of those who employ them. These habits should be carefully cultivated from the earliest years while a child's character is being developed. As the twig is bent so the tree inclines.
FitzGerald certainly showed that he had acquired the ability to learn from observation, experiment and measurement. He entered Trinity College Dublin at the young age of 16 to study his two best subjects which were mathematics and experimental science, and he was soon putting the training he had received at home to good use. At Trinity College, FitzGerald :-
... attained all the distinctions that lay in his path with an ease, and wore them with a grace, that endeared him to his rivals and contemporaries.
It was not an undergraduate career devoted entirely to study, however, for FitzGerald played a full part in literary clubs and social clubs. He also continued his athletic interests, taking to gymnastics and to racquet sports. In 1871 he graduated as the best student in both mathematics and experimental science. He won a University Studentship and two First Senior Moderatorships in his chosen topics.
The aim of FitzGerald was now to win a Trinity College Fellowship but at this time these were few and far between. He was to spend six years studying before he obtained the Fellowship he wanted, but during these years he laid the foundation of his research career. He studied the works of Lagrange, Laplace, Franz Neumann, and those of his own countrymen Hamilton and MacCullagh. In addition he absorbed the theories put forward by Cauchy and Green. Then, in 1873, a publication appeared which would play a major role in his future. This was Electricity and Magnetism by Maxwell which, for the first time, contained the four partial differential equations, now known as Maxwell's equations. FitzGerald immediately saw Maxwell's work as providing the framework for further development and he began to work on pushing forward the theory.
It is worth noting that FitzGerald's reaction to Maxwell's fundamental paper was not that of most scientists. Very few seemed to see the theory as a starting point, rather most saw it only as a means to produce Maxwell's own results. It is a tribute to FitzGerald's insight as a scientist that he saw clearly from the beginning the importance of Electricity and Magnetism. Maxwell's theory was for many years, in the words of Heaviside, "considerably underdeveloped and little understood" but a few others were to see it in the same light as FitzGerald including Heaviside, Hertz and Lorentz. FitzGerald would exchange ideas over the following years with all three of these scientists.
During the six years he spent working for the Fellowship, FitzGerald also studied metaphysics, a topic which he had not formally studied as an undergraduate, and he was particularly attracted to Berkeley's philosophy. His liking for metaphysics and his deep understanding of the topic combined with his other great talents in his future career. He won his Fellowship and became a tutor at Trinity College Dublin in 1877. This was not his first attempt at winning a Fellowship, rather it was his second since he failed to win a Fellowship at his first attempt. At Trinity College he was attached to the Department of Experimental Physics and soon he was exerting the greatest influence on the teaching of the physical sciences in the College.
In 1881 John R Leslie, the professor of natural philosophy at Dublin, died and FitzGerald succeeded him to the Erasmus Smith Chair of Natural and Experimental Philosophy. At the time of his appointment he gave up his duties as College tutor, a role in which he had been extremely successful, to concentrate on his duties as a professor. One of FitzGerald's long running battles at Trinity College Dublin was to increase the amount of teaching of experimental physics. He soon set up classes in an old chemical laboratory that he was able to obtain for his use, and he gathered round him colleagues who would help in the practical aspects of the subject. As is so often the case in universities, however, he was restricted in the progress he could make from a lack of funds.
In a lecture which he gave to the Irish Industrial League in 1896 FitzGerald emphasised his lifelong belief in practical studies:-
The fault of our present system is in supposing that learning to use words teaches us to use things. This is at its best. It really does not even teach children to use words, it only teaches them to learn words, to stuff their memories with phrases, to be a pack of parrots, to suffocate thought with indigestible verbiage. Take the case of experimenting. How can you teach children to make careful experiments with words? Yet it is great importance that they should be able to learn from experiments.
However, practical applications are built on theoretical foundations and FitzGerald fully understood this. In his inaugural lecture on 22 February 1900 as President of the Dublin Section of the Institution of Electrical Engineers, he spoke of how electricity had been applied to the benefit of mankind during the nineteenth century. Behind a practical invention such as telegraphy there was a wealth of theoretical work:-
... telegraphy owes a great deal to Euclid and other pure geometers, to the Greek and Arabian mathematicians who invented our scale of numeration and algebra, to Galileo and Newton who founded dynamics, to Newton and Leibniz who invented the calculus, to Volta who discovered the galvanic coil, to Oersted who discovered the magnetic actions of currents, to Ampère who found out the laws of their action, to Ohm who discovered the law of resistance of wires, to Wheatstone, to Faraday, to Lord Kelvin, to Clerk Maxwell, to Hertz. Without the discoveries, inventions, and theories of these abstract scientific men telegraphy, as it now is, would be impossible.
We should also look at FitzGerald's idea of the purpose of a university since it was, like his other educational beliefs, the driving force in how he carried out his professorial duties. He believed that the primary purpose of a university was not to teach the few students who attended but, through research, to teach everyone. He wrote in 1892:-
The function of the University is primarily to teach mankind. .. at all times the greatest men have always held that their primary duty was the discovery of new knowledge, the creation of new ideas for all mankind, and not the instruction of the few who found it convenient to reside in their immediate neighbourhood. ... Are the Universities to devote the energies of the most advanced intellects of the age to the instruction of the whole nation, or to the instruction of the few whose parents can afford them an - in some places fancy - education that can in the nature of things be only attainable by the rich?
As can be seen from the quotations we have given from FitzGerald's writing, his interest in education went well beyond the narrow confines of his own department. It was not merely a theoretical interest for, true to his own beliefs, he took a very practical role in education. He was an examiner in physics at the University of London beginning in 1888 and he served as a Commissioner of National Education in Ireland in 1898 being concerned with reforming primary education in Ireland. As part of this task he travelled to the United States on a fact finding tour in the autumn of 1898. As one might have expected, his aim was to bring far more practical topics into the syllabus of primary schools. At the time of his death he was involved in the reform of intermediate education in Ireland and he also served on the Board which was considering technical education.
In 1883 FitzGerald married Harriette Mary Jellett. She was the daughter of the Rev J H Jellett, the Provost of Trinity College and an outstanding scientist who had been awarded the Royal Medal by the Royal Society. It was through his personal friendship with Jellett, and also their joint scientific studies, that FitzGerald got to know Harriette. Although the couple had been married just under eight years at the time of FitzGerald's death, they had eight children during this time; three sons and five daughters. FitzGerald was elected a Fellow of the Royal Society in 1883 and, like his father-in-law, he was to receive its Royal medal. This was in 1899 when the prestigious award was made to FitzGerald for his contributions to theoretical physics, especially to optics and electrodynamics. Lord Lister, presenting the medal, said :-
His critical activity pervades an unbounded field, enlivened and enriched throughout by the fruits of a luxuriant imagination.
We should now examine the research for which FitzGerald received these honours.
Beginning in 1876, before he obtained his Fellowship, FitzGerald began to publish the results of his research. His first work On the equations of equilibrium of an elastic surface filled in cases of a problem studied by Lagrange. His second paper in the same year was on magnetism and he then, still in the year 1876, published On the rotation of the plane of polarisation of light by reflection from the pole of a magnet in the Proceeding of the Royal Society. He had already begun to contribute to Maxwell's theory and, as well as theoretical contributions, he was conducting experiments in electromagnetic theory. His first major theoretical contribution was On the electromagnetic theory of the reflection and refraction of light which he sent to the Royal Society in October 1878. Maxwell, in reviewing the paper, noted that FitzGerald was developing his ideas in much the same general direction as was Lorentz.
At a meeting of the British Association in Southport in 1883, FitzGerald gave a lecture discussing electromagnetic theory. He suggested a method of producing electromagnetic disturbances of comparatively short wavelengths:-
... by utilising the alternating currents produced when an accumulator is discharged through a small resistance. It would be possible to produce waves of as little as 10 metres wavelength or less.
So FitzGerald, using his own studies of electrodynamics, suggested in 1883 that an oscillating electric current would produce electromagnetic waves. However, as he later wrote:-
... I did not see any feasible way of detecting the induced resonance.
In 1888 FitzGerald addressed the Mathematical and Physical Section of the British Association in Bath as its President. He was able to report to British Association that Heinrich Hertz had, earlier that year, verified this experimentally. Hertz had verified that the vibration, reflection and refraction of electromagnetic waves were the same as those of light. In this brilliant lecture, given to a general audience, FitzGerald described how Hertz:-
... has observed the interference of electromagnetic waves quite analogous to those of light.
After his appointment to the chair, FitzGerald had continued to produce many innovative ideas but no major theories. For example despite his ideas on electromagnetic waves he had not followed through the research and the final experimental verification had been achieved by Hertz. The reason for this is perhaps best understood with a quotation from a letter which FitzGerald sent to Heaviside on 4 February 1889 (see for example ):-
I admire from a distance those who contain themselves till they worked to the bottom of their results but as I am not in the very least sensitive to having made mistakes I rush out with all sorts of crude notions in hope that they may set others thinking and lead to some advance.
Although FitzGerald is modestly talking down his contributions in this quotation, the comment he made about himself is essentially correct. O J Lodge  gives a similar, but fairer, analysis of FitzGerald's work:-
... the leisure of long patient analysis was not his, nor did his genius altogether lie in this direction: he was at his best when, under the stimulus of discussion, his mind teemed with brilliant suggestions, some of which he at once proceeded to test by rough quantitative calculation, for which he was an adept in discerning the necessary data. The power of grasping instantly all the bearings of a difficult problem was his to an extraordinary degree ...
Again Heaviside wrote (see for example ):-
He had, undoubtedly, the quickest and most original brain of anybody. That was a great distinction; but it was, I think, a misfortune as regards his scientific fame. He saw too many openings. His brain was too fertile and inventive. I think it would have been better for him if he had been a little stupid -- I mean not so quick and versatile, but more plodding. He would have been better appreciated, save by a few.
Finally we should examine the contribution for which FitzGerald is universally known today. There had been many attempts to detect the motion of the Earth relative to the aether, a medium in space postulated to carry light waves. A A Michelson and E W Morley conducted an accurate experiment to compare the speed of light in the direction of the Earth's motion and the speed of light at right angles to the Earth's motion. Despite the difference in relative motion to the aether, the velocity of light was found to be the same. In 1889, two years after the Michelson-Morley experiment, FitzGerald suggested that the shrinking of a body due to motion at speeds close to that of light would account for the result of that experiment. Lodge  writes that the idea:-
... flashed on him in the writer's study at Liverpool as he was discussing the meaning of the Michelson-Morley experiment.
Lorentz, independently in 1895, gave a much more detailed description of the same kind. It was typical of these two great men that both were more than ready to acknowledge the contribution of the other, but there is little doubt that each had the idea independently of the other. The FitzGerald-Lorentz contraction now plays an important role in relativity.
Sadly FitzGerald died at the age of only 49 years. Maxwell, whose work had proved so fundamental for FitzGerald, had died at the age of 48 while Hertz died at the age of 36. In fact in 1896 FitzGerald had reviewed the publication of Hertz's Miscellaneous Papers for Nature after Hertz's death. Four years later, in September 1900, FitzGerald began to complain of indigestion and began to have to be careful what he ate. A few weeks later he complained that he was finding it difficult to concentrate on a problem. His health rapidly deteriorated and despite having an operation the end came quickly.
W Ramsay, on hearing of FitzGerald's death wrote (see ):-
... to me, as to many others, FitzGerald was the truest of true friends; always interested, always sympathetic, always encouraging, whether the matter discussed was a personal one, or one connected with science or with education. And yet I doubt if it were these qualities alone which made his presence so attractive and so inspiring. I think it was the feeling that one was able to converse on equal terms with a man who was so much above the level of one's self, not merely in intellectual qualities of mind, but in every respect. ... he had no trace of intellectual pride; he never put himself forward, and had no desire for fame; he was content to do his duty. And he took this to be the task of helping others to do theirs.
FitzGerald was described by Lord Kelvin (William Thomson) as (see ):-
... living in an atmosphere of the highest scientific and intellectual quality, but always a comrade with every fellow-worker of however humble quality.... My scientific sympathy and alliance with him have greatly ripened during the last six or seven years over the undulatory theory of light and the aether theory of electricity and magnetism.
On his death the Faculty of Science of the University of London adopted the resolution :-
That this meeting ... having heard with profound sorrow of the premature death of the late Professor George Francis FitzGerald, desires to place on record its high appreciation of his brilliant qualities as a man, as a teacher, as an investigator, and as a leader of scientific thought ...
Article by: J J O'Connor and E F Robertson