ASTRONOMERS.
William Parsons, Earl of Rosse (b. in York 1800, d. 1867), F.R.S., was a very distinguished astronomer who experimented in fluid lenses and made great improvements in casting specula for reflecting telescopes. From 1842-45 he was engaged upon the construction, in his park at Parsonstown, of his great reflecting telescope 58 feet long. This instrument, which cost £30,000, long remained the largest in the world. He was president of the Royal Society from 1848 to 1854.
Sir Howard Grubb (b. 1844), F.R.S., is known all over the world for his telescopes and for the remarkable advances which he has made in the construction of lenses for instruments of the largest size.
Sir Robert Ball (b. in Dublin 1840, d. 1913), F.R.S. Originally Lord Rosse's astronomer at Parsonstown, he migrated as professor to Trinity College, Dublin, and subsequently became Lowndean Professor of Astronomy at Cambridge. He was a great authority on the mathematical theory of screws, and his popular works on astronomy have made him known to a far wider circle of readers than those who can grapple with his purely scientific treatises.
William Edward Wilson (b. Co. Westmeath 1851, d. 1908), F.R.S. A man of independent means, he erected, with the help of his father, an astronomical observatory at his residence. In this well-equipped building he made many photographic researches, especially into the nature of nebulae. He also devoted himself to solar physics, and wrote some remarkable papers on the sudden appearance in 1903 of the star Nova Persei. He was the first to call attention to the probability that radium plays a part in the maintenance of solar heat. In fact, the science of radio-activity was engaging his keenest interest at the time of his early death.
A.A. Rambaut (b. Waterford 1859), F.R.S., formerly Astronomer Royal for Ireland and now Radcliffe Observer at Oxford, is one of the leading astronomers of the day.
PHYSICISTS.
Lord Kelvin, better known as Sir William Thompson (b. Belfast 1824, d. 1907), F.R.S. Amongst the greatest physicists who have ever lived, his name comes second only to that of Newton. He was educated at Cambridge, became professor of natural philosophy in Glasgow University in 1846, and celebrated the jubilee of his appointment in 1896. To the public his greatest achievement was the electric cabling of the Atlantic Ocean, for which he was knighted in 1866. His electrometers and electric meters, his sounding apparatus, and his mariners' compass are all well-known and highly valued instruments. To his scientific fellows, however, his greatest achievements were in the field of pure science, especially in connection with his thermodynamic researches, including the doctrine of the dissipation or degradation of energy. To this brief statement may be added mention of his work in connection with hydrodynamics and his magnetic and electric discoveries. His papers in connection with wave and vortex movements are also most remarkable. He was awarded the Royal and Copley medals and was an original member of the Order of Merit. He received distinctions from many universities and learned societies.
George Francis Fitzgerald (b. Dublin 1851, d. 1901), F.R.S., was fellow and professor of natural philosophy in Trinity College, Dublin, where he was educated. He was the first person to call the attention of the world to the importance of Hertz's experiment. Perhaps his most important work, interrupted by his labors in connection with education and terminated by his early death, was that in connection with the nature of the ether.
George Johnston Stoney (b. King's Co. 1826, d. 1911), F.R.S., after being astronomer at Parsonstown and professor of natural philosophy at Galway, became secretary to the Queen's University and occupied that position until the dissolution of the university in 1882. He wrote many papers on geometrical optics and on molecular physics, but his great claim to remembrance is that he first suggested, "on the basis of Faraday's law of Electrolysis, that an absolute unit of quantity of electricity exists in that amount of it which attends each chemical bond or valency and gave the name, now generally adopted, of electron to this small quantity." He proposed the electronic theory of the origin of the complex ether vibrations which proceed from a molecule emitting light.