Archibald Hill

Archibald Hill: The Mathematician Who Measured Muscle

Archibald Vivian Hill won a Nobel Prize for detecting the heat given off by a contracting muscle — quantities so small that he had to improve the thermocouple before he could see them at all. He had already written down, as a young man, the equation that still describes how oxygen binds to haemoglobin. He also ran a wartime gunnery unit nicknamed "Hill's Brigands," sat on the committee that produced radar, and helped rescue nine hundred academics from Nazi Germany.

Bristol and Cambridge

Hill was born on 26 September 1886 in Bristol to Jonathan Hill and Ada Priscilla Rumney. He was educated at Blundell's School and went to Trinity College, Cambridge, where he read mathematics and came out third wrangler — among the very top of his year in the most punishing examination in Britain.

Then he switched to physiology. The move defined him: he brought to biology a mathematician's insistence that a phenomenon is not understood until it is expressed as a quantity.

In 1913 he married Margaret Neville Keynes, daughter of the economist John Neville Keynes and sister of John Maynard Keynes and the surgeon Geoffrey Keynes. Their four children all became scholars: Polly Hill an economist, David Keynes Hill a physiologist, Janet Hill a child psychiatrist, and Maurice Hill an oceanographer.

The Equations

Hill's first contributions arrived before he had finished his training. In 1909, still an undergraduate, he derived the relation now known as the Langmuir equation while studying how nicotine and curare bind at the neuromuscular junction. In 1910 he formulated the Hill equation, describing how oxygen binds to haemoglobin.

The Hill equation remains standard in biochemistry a century later. Its exponent — the Hill coefficient — measures cooperativity, the degree to which binding at one site changes the affinity of the others, expressed as departure from Michaelis-Menten kinetics. It is the ordinary tool for describing how a molecule responds to a signal, and a young man derived it before he had a career.

Hill's Brigands

The First World War took him out of the laboratory. Hill served as musketry officer of the Cambridgeshire Regiment, and in late 1915 joined the Ministry of Munitions. Anti-aircraft gunnery in 1915 was largely guesswork, chiefly because nobody could reliably determine an aircraft's height. Hill devised a two-mirror method to measure it, and assembled the Anti-Aircraft Experimental Section — the group that became known as "Hill's Brigands" — which produced accurate range tables for anti-aircraft guns. He was appointed OBE in 1918.

Heat in the Muscle

In 1920 Hill took the chair of physiology at the Victoria University of Manchester and turned to the question that would win him the Nobel: what happens, energetically, when a muscle contracts?

Using thermocouple equipment he had improved himself, he made exacting measurements of the heat a muscle releases. The result was clean and decisive. Heat is produced during contraction, which requires an investment of chemical energy; it is not produced during relaxation, which is passive. Muscle was thereby placed inside the ordinary accounting of thermodynamics — a machine converting chemical energy into work and heat, with a measurable ledger.

In 1922 he introduced two concepts that have never left exercise physiology: maximal oxygen uptake and oxygen debt. Every modern measure of athletic capacity descends from them. His work ran in parallel with Otto Fritz Meyerhof's on the chemistry of the same process, and in 1922 the two shared the Nobel Prize in Physiology or Medicine, Hill's citation reading "for his elucidation of the production of heat and mechanical work in muscles."

Founding a Discipline

Hill became professor at University College London in 1923 and stayed until his retirement in 1951, the year he established a Department of Biophysics there. He is regarded, alongside Hermann Helmholtz, as a founder of biophysics — the insistence that living tissue obeys physical law and can be instrumented accordingly.

The honours followed steadily: Fellow of the Royal Society in 1918, the Royal Medal in 1926, the Actonian Prize in 1928, foreign membership of the American Academy of Arts and Sciences in 1934 and the American Philosophical Society in 1938, Companion of Honour in 1946, and the Copley Medal in 1948.

Rescue

In 1933, as Hitler took power and German universities began expelling Jewish scholars, Hill co-founded the Academic Assistance Council with William Beveridge and Lord Rutherford. By the outbreak of war it had saved 900 academics from Nazi persecution; eighteen of them went on to win Nobel Prizes. His grandson Nicholas Humphrey recalled that Hill's Highgate house regularly hosted eighteen exiled Nobel laureates at a time.

Hill kept a toy figure of Hitler in his laboratory, explaining that it stood for his gratitude for the scientists Germany had handed him. "Laughter," he said, "is the best detergent for nonsense."

Parliament and a Second War

He served on the 1935 committee that developed radar, alongside Patrick Blackett and Henry Tizard. From 1940 to 1945 he sat in the House of Commons as independent Member of Parliament for Cambridge University. Posted to the British Embassy in Washington in 1940, he pushed for scientific cooperation and persuaded his own government to share its research with officials of a still-neutral United States — atomic weapons work excepted. He also worked to free refugee scientists Britain had interned as enemy aliens.

Between November 1943 and April 1944 he toured India surveying its scientific research; his recommendations helped shape the establishment of the Indian Institutes of Technology.

Last Years

Hill presided over the British Association for the Advancement of Science in 1952 and the Marine Biological Association from 1955 to 1960. He retired to Cambridge in 1967 and gradually lost the use of his legs. He died there on 3 June 1977, aged ninety, held in deep affection by more than a hundred scientific descendants around the world. English Heritage placed a blue plaque at his Highgate home on 9 September 2015.

Why Hill Matters

Hill made physiology quantitative. He measured energy in muscle to a precision nobody had achieved, he gave biochemistry an equation still in daily use, and he founded a department and a discipline to carry the method forward. Then he spent the rest of his life applying the same seriousness to problems outside the laboratory — anti-aircraft fire, radar, wartime alliance, and the lives of nine hundred scholars a government wanted destroyed.