‘We are now able to look ten thousand times deeper into the structure of the matter that makes up our universe than when we had to depend on the microscope alone’,
Sir William Henry Bragg.
In 1915, University of Adelaide mathematics and physics lecturer, William Henry Bragg and his son Lawrence (William Lawrence), a graduate of the same fields, certainly had something to brag about. The duo was jointly awarded a Nobel Prize for their discovery and experimentation of X-ray crystallography. Their discovery was so significant that 100 years on it still effects many aspects of our lives—from determining the structure of DNA and proteins, to developing new drugs and chemicals. As the only father and son combination to have been awarded the prestigious Nobel Prize, they are today recognised as one of the most scientifically brilliant teams in history.
William and Lawrence had different interests and expertise, each bringing unique skills to the partnership. William had a strong experimental background and in 1886 he took the first X-ray images in South Australia. Lawrence held a deep interest in crystals and atomic reflection. It was not until 1912 that their joint interest in X-ray diffraction was sparked. Both were intrigued by the work of German physicist Max von Laue, who proved that X-rays were waves of light with a very short wavelength. Von Laue established this by diffracting the rays through crystals.
By extending on the work of von Laue, William constructed an X-ray spectrometer that enabled the Bragg pair to examine X-rays from crystals at various angles. Through analysing a variety of substances, Lawrence developed a simplified calculation, now known as Braggs Law, to determine the structure of a crystal. Through his study, Lawrence also showed that sodium chloride in solution was made up of ions and not molecules. This was fundamental to the understanding of solutions. Together, the Braggs initiated the scientific technique of X-ray crystallography and to this day, it is still the most accurate way of determining molecular structures.
The impact of the Braggs’ work has been far reaching. Today, X-ray crystallography is used across many fields and applications of science including: medicine and pharmacy, physics, chemistry, mining and biological sciences. In particular, it has influenced the manufacture of medicines, informed how drugs such as aspirin work and has enabled HIV drugs to be developed. But the greatest breakthrough resulting from X-ray crystallography was use of the technique to establish the structure of DNA – the building blocks of life.
Baroness Susan Greenfield, the recent Director of the Royal Institution of London best surmised the significance of the Braggs’ discovery when she said, ‘The Braggs’ contribution was the first step towards the mapping of the genome, molecular biology, and all the genetic modifications, for good or ill, that will characterise much of our lives, and much of those of our children and grandchildren in the 21st century’.
At the University of Adelaide the Braggs are recognised not only for their scientific achievements but for their contribution and involvement in university life. In his role as Professor, William Henry encouraged student activities, particularly through the formation of the Union. He also held the belief that universities should ‘act as the centre from which all education radiates’. To encourage this, he welcomed country teachers to his lectures to ensure they had access to the best and latest thinking.
He also presented a series of public lectures. His final lecture entitled the ‘mysterious X-rays’, took place before his ground breaking research.
As a graduate, Lawrence was part of the student community, but even from a young age he was exposed to his father’s teaching passion. In fact, it was Lawrence’s fractured elbow that was captured in the first X-ray images taken by William.
Today, the University honours the Braggs’ work with the ‘Braggs’ building, Bragg Laboratories and the Bragg crystallography facility. The Braggs building is the newest building on campus and a facility built to support student discovery in science and the continuation of the world-class research conducted by the Institute for Photonics and Advanced Sensing (IPAS).
Sir William Henry Bragg
William Lawrence Bragg
"The Braggs" building on North Terrace Campus