J.D. Bernal

John Desmond Bernal FRS was an Irish scientist who pioneered the use of X-ray crystallography in molecular biology. He published extensively on the history of science. In addition, Bernal wrote popular books on science and society. He was a communist activist and a member of the Communist Party of Great Britain (CPGB).

His family was Irish, of mixed Spanish, Portuguese, and Italian Sephardic origin on his father's side (his grandfather Jacob Genese, properly Ginesi, had adopted the family name Bernal of his paternal grandmother around 1837). His father, Samuel Bernal, had been raised as a Catholic in Limerick and, after graduating from Albert Agricultural College, spent 14 years in Australia before returning to Tipperary to buy a farm, Brookwatson, near Nenagh, where Bernal was brought up. His American mother, née Elizabeth Miller, whose mother was from Antrim, was a graduate of Stanford University and a journalist and had converted to Catholicism. Elizabeth was raised Protestant and would send John to a Protestant school in his youth.

Bernal was educated in England first for one term at Stonyhurst College, which he hated, and so he was moved to Bedford School at the age of 13. There, according to Goldsmith, from 1914 to 1919 and found it "extremely unpleasant" and most of his fellow students "bored him," but his younger brother Kevin, who was also there, was "some consolation," and Brown claims that "he seemed to adjust easily to life" there. In 1919, he went to Emmanuel College, Cambridge, with a scholarship.

At Cambridge, Bernal read both mathematics and science for a Bachelor of Arts degree in 1922, which he followed by another year of natural sciences. He taught himself the theory of space groups, including the quaternion method, which became the mathematical basis of a lengthy paper on crystal structure for which he won a joint prize with Ronald G.W. Norrish in his third year. At Cambridge, he also became known as "Sage," a nickname given to him about 1920 by a young woman working in Charles Kay Ogden's Bookshop at the corner of Bridge Street.