Two scientists who were the first to photograph the atomic world will be honoured tomorrow. Neil Hudson reports
If you’ve watched a science fiction film recently, it’s odds on you will have been treated to one of those special effects sequences showing the workings of things which are so small they are not even visible through a microscope. We are talking about the life of atoms and molecules - also known as the nanosphere - with which, thanks to countless films and television programmes, we are all now abundantly familiar.
Think the structure of DNA, all those nightmarish black and white images of magnified bed bugs and pretty much any CGI clip involving the world of the extremely small.
None of this would have been possible were it not for the groundbreaking work of a father and son team from Leeds - Professor William Bragg and his son Lawrence, whose pioneering work involving x-ray crystallography allowed us, for the first time, to peer into the universe of the sub-atomic.
Their achievement has been described as being on a par with Albert Einstein’s special theory of relativity - indeed, it came in the same year - but despite winning the Nobel Prize for physics in 1915, it was largely overlooked, due, in part to the First World War, which was by then in full swing. Tomorrow, however, 100 years after their momentous discovery, the pair will be honoured with the unveiling of a bust of William at the University of Leeds. A replica will also be unveiled at the same time at the university in Adelaide, Australia, where William began his academic career.
Nobel prize winner Max Perutz summed up the significance of the father and son team, saying: “Why water boils at 100 degrees and methane at -161 degrees, why blood is red and grass is green, why diamond is hard and wax is soft, why graphite writes on paper and silk is strong, why glaciers flow and iron gets hard when you hammer it, how muscles contract, how sunlight makes plants grow and how living organisms have been able to evolve into ever more complex forms... the answers to all these problems have come from structural analysis.”
The keys to structural analysis were first cut by William Bragg, professor of physics at the University of Leeds, and his 23-year-old son Lawrence when they discovered in a series of experiments in 1912-14 that by firing x-rays through crystals and plotting the emerging patterns on photographic plates, they could see for the first time structure of materials at an atomic level. It is no overstatement to say that x-ray crystallography was one of the most powerful scientific tools of the 20th Century, allowing scientists to peer into the structure of materials.
X-ray crystallography was first developed in Leeds. Lawrence Bragg, a junior researcher at Cambridge, had suggested the concepts behind X-ray crystallography in 1912 but, frustrated with poor equipment at Cambridge, came up to Leeds in the 1912-13 Christmas holidays to develop the technique on the first x-ray spectrometer, which had been designed by his father. As the exciting results started to roll in, Lawrence spent much of 1913 in Yorkshire. He was signed off from Trinity College Cambridge to spend the whole of the Michaelmas term (October through December 1913) in his father’s labs and later recalled: “We got some spectacular results with (the spectrometer) and we joined forces. It was obvious that, working together on the ideas I had and the ideas he had, there were great prospects of some very exciting results indeed and I went and researched in Leeds.”
He recalled: “It was a wonderful time, like discovering a new goldfield where nuggets could be picked up on the ground, with thrilling new results almost every week, until the war stopped our work together.”
The father and son team would have breakfast together at the family home in Headingley, and would walk down Grosvenor Road, down a ginnel to Hyde Park Corner and along Woodhouse Lane or across the park to the University’s “physics sheds,” near the current Parkinson building, where Lawrence Bragg remembered “we worked far into every night with new worlds unfolding before us in the silent laboratory.”
The technique is still vital to work across academia and industry. According to Prof Andrew Bell, Professor of Electronic Materials at the University of Leeds: “The world would not be the same without their work. The medical ultrasound device that lets you see your baby in the womb, the sonar on a submarine, the fuel injectors in your car all use materials developed using these techniques. We would not know what we do about the structure of everyday materials around us, about the way our bodies work, about genetics. Our knowledge in biology, materials science, electronic materials, pharmacology and many other areas relies on X-ray diffraction.”
Some of the most profound scientific discoveries of the modern era have stemmed directly from the Braggs’ efforts: Watson and Crick’s work on the helical structure of DNA (Rosalind Franklin’s famous Photograph 51 recently dramatized with Nicole Kidman was an x-ray crystallography image), Dorothy Hodgkin’s work on the structures of biochemical molecules including penicillin, Max Perutz’s work on haemoglobin, the list goes on.
William Hunter, biographer of Lawrence Bragg, notes: “The scientific impact of x-ray crystallography has been as great as those of quantum theory and relativity and the impact on everyday life even greater.”
Lawrence was at the battlefront in Ypres with the Royal Horse Artillery when he received a letter from his family telling him about the prize.
He wrote back: “It is so awfully nice to be coupled with Dad in this way... I got many congratulations today, everyone had seen it in the papers... Our section treats me with much more respect than before.”
So much so in fact they nicknamed him ‘Nobbler’ and his sergeant threatened to cut his beer ration, adding it might be too common a drink given his new standing.