JD Bernal

John Desmond Bernal was born on 10th May, 1901 in Nenagh, County Tipperary, Ireland. Little did anyone know at the time that he would go on to become one of the most brilliant scientists of the 20th century. His scientific acumen was evident from quite a young age: to complete the requirements for his undergraduate degree at Cambridge, Bernal used the quaternion notation to derive all the 230 crystallographic space groups. This work translated into a paper on crystal structures, quite the feat for an undergraduate, and earned him a joint prize with future Nobel Laureate Ronald G.W Norrish. He was also known to be a voracious reader who could hold discussions for long hours on various topics; it was this vast body of knowledge which earned him the nickname “sage”. In 1923, Bernal joined the lab of Nobel Laureate William Henry Bragg for his doctoral studies; the phenomenal undergraduate work no doubt played a big role in his selection! Just the next year, he went on to determine the structure of graphite, developing the use of rotating cameras and X-Ray films to measure X-Ray diffraction intensities in the process (rather than using the conventionally employed gold-leaf electroscope).

Such scientific excellence became a theme in Bernal's life, coupled with what one may only describe as wholehearted scientific magnanimity. In fact, his analysis of diffraction data with the X-Ray films required what we know today as the concept of the Ewald sphere, just that it wasn’t known at the time. So just as any brilliant budding scientist would, Bernal came up with it himself. Of course, when Paul Peter Ewald finally got around to publishing it, Sage was more than happy to give him all the credit. This kind of scientific generosity came to be a hallmark of Bernal’s personality.

When it came time to be a supervisor, Bernal had a knack for training scientists who would go on to be pathbreakers. Among them was Dorothy Hodgkin, who won the Nobel Prize in Chemistry in 1964 "for her determinations by X-ray techniques of the structures of important biochemical substances.” In fact, Ewald later told Bernal in a letter - “I think if you did nothing else in science but train this woman, your name would last forever. In one letter to her parents, Hodgkin recalled a time when she gave Bernal some data that was to be presented at a conference, just as they were about to leave for that very conference! The story goes that Sage was deeply engrossed in the papers right up to the moment when he got up to speak. Hodgkin remembers being astounded at his fantastic presentation, which gave the impression that he had worked with the results for weeks, rather than just seeing them hours before. Another one of Bernal’s illustrious students was the famous crystallographer Max Perutz (also a Nobel Laureate), who solved the structure of hemoglobin (a protein which had chosen to work on during his graduate studies) after many years of toil.

Despite never being awarded the Nobel Prize himself, J.D Bernal is regarded by many to be one of the pioneers of the field of Molecular Biology, and one of the first to use X-Ray diffraction to determine protein structures. Despite all this, science was just one aspect of Bernal’s multifaceted life. Perhaps his extensive writing and contributions to the D-Day invasion of Normandy would be apt starting points for the curious reader!