Ernest Starling: A Life in Five Chapters

Chapter 1 · Guy's, and a Man Who Would Not Be Quiet

A physiologist with a low opinion of British medicine

1866 – 1899 · London · Guy's Hospital · Breslau · University College London

Ernest Henry Starling was born in London in April 1866. His father was a clerk of the Crown in Bombay and was largely absent; Starling was brought up in London by his mother.

He trained at Guy's Hospital, qualified in medicine, and immediately turned to physiology rather than practice. He spent periods in German laboratories — Breslau under Rudolf Heidenhain, and elsewhere — and came back with a low opinion of how research and medical teaching were organised in Britain compared with Germany.

He said so, repeatedly, for the rest of his life, in print and in public. He thought British medical education was run by clinicians who did no research, that hospital appointments went by social connection, and that the whole system was complacent. He was substantially right and he made permanent enemies.

In 1899 he took the chair of physiology at University College London, where he stayed.

His first major work, in 1896, was on the capillary. He worked out the balance of forces governing fluid movement across a capillary wall: blood pressure pushes fluid out at the arterial end, while the proteins in the plasma exert an osmotic pull drawing it back in at the venous end. The balance between them determines the tissue fluid bathing the cells — and, when it goes wrong, produces swelling. These are the Starling forces, and they are why a person with low blood protein swells.

Why this matters

The Starling forces explain how tissue fluid forms and why swelling occurs, and they remain the standard account of exchange at a capillary.

You have the capillary and the critic of British medicine. What would you ask?

Ask Starling

• “What forces decide whether fluid leaves a capillary?”
• “Why does someone with low blood protein swell?”
• “What did German laboratories have that British ones did not?”
• “Was it worth making enemies of the establishment?”
• “Why abandon clinical practice for the laboratory?”

Chapter 2 · Every Nerve Cut

16 January 1902

1902 · University College London

Ivan Pavlov, the most authoritative physiologist alive, had established that the pancreas secretes digestive juice in response to a *nervous* reflex: acid arriving in the intestine stimulates nerves, the message goes to the brain and back, and the pancreas responds. Pavlov's work on nervous control of digestion won him the Nobel Prize in 1904.

On 16 January 1902 Starling and William Bayliss — his colleague, his closest collaborator and his brother-in-law, Bayliss having married Starling's sister — tested it properly.

They took an anaesthetised dog and cut *every* nerve running to a loop of its small intestine, leaving only the blood vessels intact. On Pavlov's account nothing could now happen: the reflex arc was destroyed.

They introduced acid into the denervated loop.

The pancreas secreted.

With no nervous connection remaining, the message could only have travelled in the blood. They then took a scraping of intestinal lining, ground it up with sand and acid, filtered it, and injected the extract into a vein — and the pancreas secreted again. There was a *substance*. They called it *secretin*.

The candour of what followed is worth recording. Starling wrote that they had, of course, both had the idea years before and never tested it. Pavlov, when told, had the experiment repeated in his own laboratory, watched the result, and accepted that he had been wrong.

“These chemical messengers may be conveniently called hormones.”

— Ernest Starling, Croonian Lectures, Royal College of Physicians (1905)

Why this matters

Cutting every nerve and getting a response anyway is a clean, decisive experiment: it eliminates one mechanism entirely and leaves only one possibility.

You have the cut nerves and the pancreas responding anyway. What is your question?

Ask Starling

• “Why cut every nerve rather than some of them?”
• “How did you get from 'not nerves' to 'a substance'?”
• “What did Pavlov do when he heard?”
• “You had the idea years earlier — why not test it?”
• “How much of this was Bayliss's work?”

Chapter 3 · One Word, and a Whole Discipline

Croonian Lectures, 1905

1905 · London · Royal College of Physicians

Secretin was one substance. Starling's contribution in 1905 was to see that it could not be the only one.

In his Croonian Lectures he generalised: there exists a whole *class* of chemical messengers, produced in one organ, carried in the blood, and acting on a distant organ to command it. He proposed a name, taking advice from classicists at Cambridge, from the Greek *hormao* — I arouse, I set in motion.

*Hormone*.

Coining the word did something more than label a substance. It asserted that a category exists, and it invited a search. Within three decades adrenaline, thyroxine, insulin, the sex hormones and the pituitary hormones had all been identified, and endocrinology was a discipline.

It is a rare case of a term creating a field rather than describing one already there.

It is worth noting how little Starling actually knew. He had no idea what hormones are chemically — that some are proteins, some steroids, some modified amino acids. He had no idea how a target organ recognises one; receptors were unknown. He had no concept of feedback control, which is how hormone levels are actually regulated.

What he had was the right general claim: chemistry carried in the blood can command an organ as surely as a nerve can. Before 1902, the body was understood as governed by the nervous system. After 1905, it had two communication systems, and the chemical one turned out to be the older and, in some ways, the more fundamental.

Why this matters

Coining 'hormone' asserted that a whole class of chemical messengers existed, and the search that word licensed produced insulin, thyroxine and the rest within thirty years.

You have one experiment turned into a category. What would you ask him?

Ask Starling

• “Why invent a word rather than just describe secretin?”
• “What made you think there would be others?”
• “How does a target organ know a message is for it?”
• “Which is the older system — nerves or hormones?”
• “What stops a hormone level running away?”

Chapter 4 · The Brown Dog

A statue, a riot, and a laboratory on trial

1903 – 1910 · London · Battersea

In February 1903 Bayliss gave a demonstration to students at UCL involving a brown terrier. Two Swedish anti-vivisection activists, Lizzy Lind af Hageby and Leisa Schartau, had enrolled as students specifically to gather evidence, and attended.

They published an account alleging that the dog had been inadequately anaesthetised, had struggled, and had been used in more than one procedure — which, if true, was illegal under the Cruelty to Animals Act of 1876.

Stephen Coleridge of the National Anti-Vivisection Society read the account publicly. Bayliss sued him for libel and won, with Starling testifying. The jury found for Bayliss; the court accepted that the animal had been properly anaesthetised. Starling admitted in evidence that he had used the same animal in an earlier procedure, which was a technical breach.

Winning settled nothing. In 1906 anti-vivisection campaigners erected a bronze statue of the dog in Battersea, with an inscription about the men who had experimented on it and a challenge to Londoners asking how long such things would continue.

Medical students repeatedly attacked the statue. In December 1907 around a thousand of them marched on it; there were running battles with police and Battersea residents in Trafalgar Square — the Brown Dog riots. The council removed the statue in 1910 and had it destroyed.

What this shows is that the ethics of Starling's methods were contested at the time, publicly and fiercely, by people who knew what was involved. It is not a modern judgement applied backwards.

Why this matters

The Brown Dog affair shows that the ethics of animal experimentation were fought over publicly and violently in Starling's own lifetime, not only in retrospect.

You have the libel case, the statue and the riots. What is your question?

Ask Starling

• “Was the demonstration conducted lawfully?”
• “Why did winning the libel case not end the argument?”
• “What did the two Swedish students see?”
• “Why did a thousand medical students riot over a statue?”
• “Did the controversy change how you worked?”

Chapter 5 · The Law of the Heart, and No Prize

War work, reform, and a death at sea

1914 – 1927 · London · France · The Caribbean

During the First World War Starling served on the government committees dealing with food supply and rationing, applying physiology to the question of how many calories a population actually needs. He also worked on defence against poison gas, and went to France, where he clashed with the military authorities and was effectively removed for insubordination.

In 1918 he published what became known as *Starling's law of the heart*: the more the heart muscle is stretched by the blood filling it, the more forcefully it contracts, and the more it ejects. Return more blood to the heart and it will pump more — automatically, without any nervous instruction. The heart matches its output to its input by a property of the muscle itself.

He demonstrated it with the heart–lung preparation, an isolated heart kept beating with its blood supply, so that filling pressure could be varied and output measured directly.

He also spent years campaigning for the reform of British medical education, arguing that clinical medicine should be taught by people actively doing research. Much of the modern British academic medical school follows the pattern he argued for.

He was nominated for the Nobel Prize repeatedly — the records show many nominations across two decades — and never received it. Bayliss died in 1924. Starling's own health failed; he had colon cancer and heart disease.

He died on 2 May 1927 aboard ship near Kingston, Jamaica, aged sixty-one, and was buried there.

Why this matters

Starling's law says the heart matches its output to its input through a property of the muscle itself, needing no instruction from the nervous system.

You have the law, the reforms and the prize that never came. What would you ask?

Ask Starling

• “Why does a more filled heart pump harder?”
• “What did you learn from rationing a country?”
• “Did not getting the Nobel Prize matter to you?”
• “Why should clinicians do research?”
• “What would you have found next?”

What Starling changed

Endocrinology begins with Starling's experiment and his word. Secretin was the first hormone identified, and coining the term in 1905 licensed the search that produced insulin, thyroxine, adrenaline and the rest within three decades. The Starling forces governing fluid exchange at a capillary and the law relating the heart's output to its filling both still carry his name.

A debate that continues

Starling's failure to receive a Nobel Prize despite many nominations has never been fully explained, and the Brown Dog affair shows the ethics of his methods were fiercely contested in his own lifetime.

Keep exploring — ask Starling

• “Which hormone would you most like to have found?”
• “How should a scientist argue with an institution?”
• “What did Bayliss contribute that you have not been asked about?”

Related lives

• Claude Bernard — Father of Experimental Medicine
• Frederick Banting — Who Sold the Patent for a Dollar
• Santiago Ramón y Cajal — Father of Modern Neuroscience
• Richard Doll — The Man Who Proved Smoking Kills

Related themes

Hormones and the endocrine system · The heart and circulation · Tissue fluid