Much of what he deduced was right. Stopping a pig's squeals by severing its nerves made him realize that the brain controlled the voice. Aristotle had previously suggested that the brain was some sort of cooling system for the body. Galen concluded that arteries contained blood (rather than air) and that each organ had a particular function. He also advised that the strength, frequency and rhythm of the pulse could be used to diagnose disease. Indeed, he developed elaborate and complex theories on the differences between the various types of pulse that eventually stretched to sixteen books.
Some of his theories, however, were completely wrong. He taught that the blood was produced in the liver and distributed in veins. He saw the heart as some sort of furnace containing two chambers with tiny pores or micro-holes between them that allowed the blood to seep from one side to the other. There was no sense that the blood circulated around the body or was pumped from the heart. The pulsating movement of the arteries he attributed to their muscular structure, which he supposed contracted and expanded 'naturally'. And although he realized that urine was produced in the kidneys rather than the bladder, he got the position of the kidneys wrong.
Galen's crowning achievement was 'perfecting' the philosophical medical theories developed by the ancient Greeks: the four humours. Each humour corresponded to a different temperament and element: yellow bile was associated with fire; black bile with earth; phlegm with water; and blood with air. Illness occurred when the humours were out of balance. To rebalance the humours, the doctor could remove blood, induce vomiting or purge the body with an enema. A fever, for example, might be attributed to an excess of blood, so Galen advocated bloodletting to cool the body. A general feeling of melancholy suggested too much black bile, requiring the gut to be purged.
Galen believed he was a brilliant scientist and philosopher. Considering that most of his anatomical experience was based on animals, he did not do such a bad job. Many of his conclusions were based on real experimental evidence and would have made ideal foundations for later natural philosophers and doctors to refine and so improve our understanding of anatomy. The problem was that until the sixteenth century no one bothered.
The Roman Empire fell, Islam rose, Europe embarked on the Crusades, Columbus 'discovered' America, Magna Carta was signed and the printing press invented. Yet still, after one and a half thousand years, our knowledge of medicine, surgery and anatomy was based on the writings of Galen, a boastful Roman surgeon. That Galen was wrong about so much was hardly his fault, nevertheless it took more than one thousand years before doctors and surgeons began to question his teachings.
DEAD MEN'S SECRETS
Louvain, Flanders, 1536
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It was nearing dusk. The city gates were about to be shut for the night. Outside the walls of Louvain, swinging on a gibbet in the gentle evening breeze, was the macabre silhouette of one of the city's criminals. The body was still more or less intact, but you could see through the ribcage. Ligaments connected many of the bones, but the skull was snapped unnaturally to one side – evidence that the hanged man had at least died quickly from a broken neck rather than from slow strangulation. Some parts of the body had fallen to the ground, the result of scavenging dogs jumping up and tearing them off. The kneecaps had gone, as had one of the feet. Birds too had feasted on the decomposing flesh, their activities betrayed by the guano on the man's shoulder blades.
The authorities were particularly worried about undesirables arriving in Flanders from France. A decomposing corpse stationed outside the city gates sent a clear message that criminal activity would be severely punished. There was little evidence that the display worked, but it certainly unnerved most of the God-fearing citizens passing by.
This evening the road is deserted and a precocious medical student, Andreas Vesalius, is on his way home. He needs to be back in the city by the evening curfew, otherwise he will have to spend the night locked outside the city walls. He sees the gibbet at the roadside and goes across to take a closer look. The dangling corpse is exactly what he has been looking for – an ideal subject for study. Getting hold of bodies is difficult, and if he does not take this opportunity he thinks it likely that another medical student will.
The chain supporting the skeleton hangs some nine feet off the ground, and the corpse itself is considerably bigger than Vesalius. Even if he manages to get it down, he realizes he has little chance of carrying it home in one piece. With time against him, the obvious solution is to take one bit at a time, so Vesalius jumps up and grabs one of the legs. Tugging hard – it's surprising how strongly the femur is attached to the bones of the pelvis – he pulls it towards him until the ligaments rip with a hollow tearing sound and the joint pops out of its socket. He hauls it clear as the skeleton lurches to one side, dancing crazily on the end of its chain.
Vesalius then pulls off the second leg, twisting it out of its socket. The bones pile up at his feet. Next he decides to take the arms, but has to be careful not to damage the ligaments holding together the fragile bones of the hands. He also has to reach them. Fortunately, the wooden scaffold is rough and he can climb up, grabbing the swaying chain to pull the stinking corpse closer. Using one hand to steady himself, he grabs an arm with the other, gives it a sharp twist to pop it out of the joint and drops it to the ground. He then yanks the chain to spin the body round and reaches across for the second arm.
Jumping to the ground, he bundles up the bones in his cloak, like firewood, and hastens towards the city, keeping to the shadows as he makes his way home. Once there, he dumps the pile of bones on his kitchen table and, pausing only to pick up a hammer, heads back to the gibbet. He is determined to remove the rest of the body.
The head and trunk are all that remain, but the chain is attached to the top of the backbone and takes some hefty blows from the hammer before it comes free. Although he tries to catch them, these final body parts – the ribcage, pelvis and skull – fall to the ground, so he jumps down and wraps them in his cloak.
The gibbet casts a long shadow in the moonlight as Vesalius scrabbles around in the dirt to gather any stray pieces of cartilage and stuff them into his pockets.
The final challenge is to get back into the city. Night has fallen and the curfew is in place. Returning through the main gate would be foolish. Even an educated man such as Vesalius would have a hard job explaining his mission to the watch-keepers. He heads instead for another gate – one where he can slip past the guards unnoticed or, at worst, bribe them to get in.
Stealing a corpse from a gibbet might seem enough work for one night, but Vesalius is a man possessed. Safely back home, he now has a substantial collection of bones on his kitchen table – but they are starting to smell. There is more flesh on the bones than he thought. In the warmth of the kitchen, even the smoky fire can't disguise the sickly stench. Not only is this unpleasant, but the neighbours will notice. This could only lead to difficult questions. So, undeterred, Vesalius sets about stripping the corpse down to its bare bones.
After placing a large pan of water to heat on the fire, Vesalius gets a knife and scrapes away any last shreds of muscle, tendons and skin. He reaches his fingers into joints to separate out the cartilage and places this carefully to one side. When the water has boiled, he drops in the bones. He tries to keep the bones of some parts – such as the hands and feet – together as much as possible.
After a few minutes, he drains away the fat, straining the liquid to avoid losing any odd pieces of cartilage or fragments of bone. By daybreak the task is complete, the rotten flesh is discarded outside in the gutter and the bones and cartilage are gathered in an enormous pile on his kitchen table. Now all Vesalius has to do is put the skeleton back together again.
Although technically illegal, bodysnatching wasn't a wholly unusual pastime for a medical student. Few people were likely to complain if the remains of a criminal or pauper went missing. Frankly, it was doing everyone a favour. Neither was this the first time Vesalius had been involved in st
ealing a body. Desperate for some hands-on experience of anatomy, he had already joined with other young physicians to take bodies from the cemeteries of Paris when he was at medical school. But dead human bodies were difficult to come by, and Vesalius had a plan for his boiled-up bones.
In sixteenth-century Europe, Galenic medicine was as healthy as ever (unlike many of the patients who received treatment). Galen's 'scientific' writings had been recently rediscovered, translated and adapted; his theories re-examined and absorbed into the Christian doctrine for the modern European age. Medical treatment involved a thorough examination of the patient. The pulse would be read and therapy prescribed, depending on the imbalance of the humours. Just as in Galen's day if you went to the doctor with a fever there was a good chance he would get out the bleeding bowl or reach for the purgative and funnel to clear out your bowels.
But whereas the study of medicine was a respected, even noble, profession, surgeons were, as Vesalius would bemoan, considered little better than servants. There was, however, a growing fascination with anatomy. This was led, to a large extent, by artists. Renaissance artists were enthralled by the human body, its form, bone structure and musculature. And in the same way that doctors looked to Galen for insights, artists took inspiration from the beautiful statues of ancient Greek and Roman culture. A few years earlier, Leonardo da Vinci had become intrigued by the mechanics of the body. He produced intricately detailed drawings of human anatomy, of the brain, blood vessels and nervous system. Unfortunately, they remained unpublished during his lifetime.
Human dissection, almost always of criminals, was rare but gaining in popularity as part of medical training. Students were expected to attend lectures on human anatomy. At these, a professor would stand in a pulpit to read from Galen's text, while an assistant opened up the body. But these events could become awkward affairs when it became apparent that what Galen had described bore little relation to the anatomical reality of the human body. People were beginning to realize that, for all his genius, Galen had probably cut open animals rather than people. Some in the medical profession – particularly precocious medical students – were starting to question his wisdom. For surgery to develop, someone had to get a proper grip on where everything was and how it worked.
Vesalius set himself the task of reaching a fuller understanding of human anatomy. Back in his kitchen he began to sort out the bones and cartilage of the skeleton. He painstakingly identified each bone and laid it out in the correct position until his human jigsaw gradually came together. The parts that were missing, the foot and kneecaps, he 'obtained' from another corpse. There are 206 different bones in the human body, and Vesalius eventually laid out every one before carefully wiring them together into a skeleton that could be hung from a hook – not unlike the gibbet it was originally taken from.
The reconstructed skeleton was only the start. Over the next six years Vesalius dissected as many bodies as he could lay his hands on. Many were those of executed criminals; others he acquired from cemeteries. The contributions these dead people made to medicine were considerable. With their help, Vesalius was soon able to map every single organ, muscle and ligament in the human body.
Within the next few years Vesalius popularized dissection and started holding public anatomy demonstrations. These were attended by hundreds of spectators – not just medical students. Dissection became such a popular entertainment that the supply of bodies started to run out. This created a lucrative source of employment for less desirable elements of society. Working in gangs, bodysnatchers (or resurrectionists, as they would later be known in Victorian London) could make a comfortable income. However, the profession wasn't without its occupational hazards. Even if the authorities turned a blind eye, bodysnatching was still illegal. There was also the risk of picking up diseases. A small infected cut and you could soon be joining the other bodies destined for the dissecting table.
Vesalius published his work in De Humani Corporis Fabrica (The Construction of the Human Body). The invention of printing, using movable type and woodcuts, allowed him to include technically accurate and lavish illustrations. These pictures accurately identify the locations of all the major organs, nerves and muscles in the human body. The woodcuts show corpses posed in various unlikely situations, as if they are still alive. A picture revealing human muscles has the figure posed on a hillside in front of a town. There is a corpse dangling from a pulley and a skeleton resting against a tomb as if contemplating the meaning of life (or death).
The book was widely distributed and read by medical practitioners across Europe. In it Vesalius corrected more than two hundred of Galen's mistakes. These ranged from the structure of bones to the shape of the liver. In the second edition of his book, Vesalius also ruled out a connection (through Galen's micro-holes) between the two sides of the heart. However, even though he had worked out the structure of the heart, he still believed arteries originated in the heart and agreed with Galen that veins started in the liver. It was another eighty years before William Harvey concluded that the blood circulated around the body (see Chapter 2).
After 1300 years of stagnation, anatomy was finally on a firm scientific footing. Physicians and surgeons at last knew how the human body fitted together. Vesalius had broken the first barrier to the development of modern surgery. However, there were still three more barriers to go.
BLOOD ON THE BATTLEFIELD
A field near Turin, Italy, 1537
* * *
This is what happens when a musket shot hits a human body.
The bullet punctures the skin. As it does so, it drags fragments of clothing and gunpowder with it. The shot rips through the flesh, burning the tissue and splaying slivers of skin outwards. It gouges its way through the muscle, tearing apart the muscle fibres and severing tendons, veins and arteries.
As an artery wall is ruptured, blood starts to spray from the wound – pulsing at high pressure into the cavity the bullet has drilled. The bullet slows as it reaches the bone. The bone splinters, scattering sharp fragments. The two ends of the broken bone smash outwards through the skin. By now, the bullet has lost momentum and becomes lodged in the wound, mixing with the congealing bloody broth of muscle, bone, cloth and skin.
Injuries from musket bullets were far worse than anything that had been seen with daggers, swords or arrows. When a blade or arrow enters the body it inflicts a 'clean' wound and, with any luck, comes straight out again. But with the invention of the musket, and the larger guns that went with it, the battlefield was transformed. The few battlefield surgeons available had to cope with overwhelming casualties on a daily basis. When the guns opened fire and the men fell, the smoke mingled with a flume of fine red mist – blood spraying upwards from the injured and dying men.
Ambroise Paré had never seen such horror. The twenty-seven-year-old had been appointed as a battlefield surgeon to the French infantry commander at the siege of Turin. The army had been sent into northern Italy by the king, François I, in a long-running dispute over territory with the Holy Roman emperor, Charles V. By the time Paré arrived, the carnage was already horrific. To get close to the battlefield he had to ride across the bodies of dead and fatally wounded soldiers. Picking his way between them as best he could, he was forced to ignore their dying moans and pleas for help.
As Vesalius had noted, in sixteenth-century European medicine even experienced surgeons held little standing in society. The people who practised surgery were usually barbers. They had received no formal medical training and spent most of their time trimming beards or lopping off the odd wart. They might sometimes be employed to assist doctors with bloodletting. As for Paré, he was neither qualified nor registered as a surgeon. He had been working as a barber-surgeon at the largest hospital in Paris, he had no academic qualifications and no experience of anything other than the most basic surgical procedures. Everything he learnt about the profession (if it could even be described as such a thing) came from hands-on experience. He was familiar with basic anato
my and the theories of more advanced surgical techniques, such as amputation, but had not had the opportunity to put his knowledge into practice. He was going to have to learn fast.
Although the technology of war had advanced considerably over the last few centuries, battlefield surgery had changed very little. Surgeons had few options at their disposal. Any substantial wounds or compound fractures of a leg or arm usually meant the limb had to be removed. If a bullet entered a soldier's abdomen, surgeons might attempt to remove it with their fingers, or try to drain the wound of blood (and later pus as infection developed), but could do little else. For any seriously wounded soldier, the odds of survival were poor. However, surgery might give them a chance of life.
Every day Paré would saw off limbs. To stop the bleeding he used a hot cauterizing iron. As the leg or arm was removed, he placed the iron against the flesh – searing the muscle, blood vessels and skin together. Bullet wounds received the same treatment. With larger wounds, boiling oil was applied instead. Poured into the hole left by the bullet, the oil would burn everything it touched, destroying tissue but defeating blood flow. There was a belief at the time that gunpowder was poisonous, so cauterizing with an iron or pouring in hot oil had the secondary effect of destroying any poison. Or so the theory went. When bullets had failed to kill the soldiers, the shock of having boiling oil poured into their wounds often finished the job.
Blood and Guts Page 4