Royal destinations:IT IS a reasonable assumption that unless they are keen on thermal radiation, magnetism and diamagnetic polarity, to say nothing of thermopile technology and absorption spectroscopy, most Irish people will not be overly familiar with the work of John Tyndall, which says more about us than it does about him.
For Tyndall was one of Ireland's greatest physicists, a man whose contribution to human knowledge places him among the great Victorian scientists of his day, Michael Faraday included. Among the more wonderful of Tyndall's discoveries is his explanation as to why the sky is blue.
The Tyndall Institute at University College Cork, to which Queen Elizabeth will go on Friday, May 20th, her final port of call before flying out from Cork Airport, is named in his honour.
John Tyndall was born in Leighlinbridge in Carlow in 1820 where his father was a member of the Royal Irish Constabulary. The young Tyndall's early education has been likened to the hedge-school variety but, according to the institute, the expert tutelage of his teacher, John Conwill, ensured he had a solid foundations in mathematics, English composition, drawing and surveying.
After school, he worked as a surveyor for the Ordnance Survey of Ireland. Aged 27, he became a mathematics teacher at the Queenwood School in Hampshire, England. There he met the chemist Edward Frankland and they established the first widely used school teaching laboratory. The following year, 1848, Tyndall went to Marburg University in Germany from which he obtained his doctorate two years later. In 1853 he was appointed professor of natural philosophy (ie physics) at the Royal Institution in London. In 1867, he succeed Faraday as the superintendent and was responsibility for the delivery of scientific lectures to the public. Tyndall was an excellent educator, practical demonstrator of scientific phenomena and populariser of science. His major scientific interest was the study of the interaction of light with matter, especially gases. His interests spanned heat, sound, and light .
Tyndall's rigorous experimental approach was embodied in the optical methods he developed for measurement of particles, based on the idea of light scattering (the Tyndall Effect). He invented a method for the destruction of bacteria in food, called tyndallisation, which is more effective than pasteurisation. And he also invented the first fireman's respirator. In keeping with the scientifically revolutionary times in which he lives, Tyndall was a strong supporter of Charles Darwin's theory of evolution based on natural selection. He was a member of the X Club, a dining circle of like-minded individuals who sought to strengthen the barrier between religion and science.
The Tyndall Institute was set up in 2004 as a research institute bringing together complementary activities in photonics, electronics and networking research to support industry and increase the number of graduates for the knowledge economy.
Tyndall died of an accidental drug overdose aged 73, taking chloral hydrate to treat insomnia.
And so why is the sky blue? Because light is scattered by small particles suspended in the atmosphere. Short-wavelength light is absorbed by the molecules of nitrogen and oxygen that make up the atmosphere. This absorbed blue light is then radiated in different directions and gets scattered all around the sky.
Whichever direction you look, some of this scattered blue light reaches you. Since you see the blue light from everywhere overhead, the sky looks blue. This colour is known as Tyndall Blue.