The Herbalist: Nicholas Culpeper and the Fight for Medical Freedom. Benjamin Woolley

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      Galen saw ‘diastole’, the phase of the heart’s beat when it expands, as the active phase, when it mixes pneuma, or vital spirit, from the lungs with blood to vivify it. Systole, the phase when the heart contracts, was when it relaxed. Galen further concluded that, since the pulse of the arteries did not synchronize with the diastole phase, they must pulse of their own accord, in a manner similar to the ‘pulse’ of the intestine passing food through the digestive system.

      Harvey turned this idea upside down. He argued that the active phase was systole, when the heart contracted, pushing out the blood that had flowed into the heart’s chambers, or ventricles, during diastole. The pulse was thus not ‘from an innate faculty of the arteries, as according to Galen’, but the pressure wave produced by the heart pumping blood at high pressure into the arteries, which explained why they had walls thicker than those of veins.⁶³ ‘From the structure of the heart it is clear that the blood is constantly carried through the lungs into the aorta as by two clacks of a water bellows to raise water,’ Harvey concluded. He was referring to the system of valves used to fill a pair of bellows with water, which is then squirted out under pressure.

      He used another experiment to show where the blood goes to once it has left the heart. Physicians were familiar with applying ‘bandages’ (tourniquets) to the upper arm for blood-letting. They would know how a tourniquet applied very tightly would cut off both veins (which run just beneath the surface of the skin) and arteries (which are deeper in the arm), while a looser tourniquet would restore the flow of the arteries (indicated by the return of the pulse in the wrist) but not of the veins. Harvey noted that when the tourniquet is applied at its tightest, the hand would turn cold, but when it was loosened sufficiently to restore flow through the arteries it would become flushed and swollen, with the veins standing out. The hand would remain in that state while the tourniquet remained in place, with no sign of the engorgement dispersing, which is what would have been expected if the venal blood was consumed. But when flow was restored to the veins by releasing the tourniquet altogether, the swelling would disappear instantly. Thus, ‘by [application of] a bandage it is clear that there is a transit of blood from the arteries into the veins, whereof the beat of the heart produces a perpetual circular motion of the blood’. In other words, blood did not seep out into the extremities of the body to be turned into living tissue, but circulated around, pumped by the heart. This meant that Galen was wrong, not only about the heart, but about the liver also, and it raised serious questions about the role of blood. If it was not the fuel that fed as well as animated the body, what was it for? On this, Harvey for the time being held to the Galenic belief that it was something to do with delivering ‘natural heat’, the vital spirit that animated the body. The heart’s two chambers were ‘two cisterns of blood and spirit’, as he put it, and the role of the circulation was to ensure the even distribution of these products through the body.⁶⁴

      Charles Darwin wrote to a friend that to publish his theory of evolution by natural selection was ‘like confessing to a murder’.⁶⁵ Harvey’s confession was no less dangerous. According to the dating evidence of his lecture notes, he first explained his theory in January 1618. This was eight years after Galileo, who had held the chair of mathematics at Padua at the time Harvey had studied there, had used a telescope to confirm Copernicus’ theory that the earth went round the sun, and just three years after the Catholic Inquisition had formally declared Copernicanism to be heretical. And it was only eighteen years after the philosopher and mystic Giordano Bruno was burned at the stake in Rome for suggesting, among other speculations, that the blood must go round the body as the planets go round the sun.

      Harvey faced no such extreme reaction to his theory. In fact, there was barely any reaction at all, merely a respectful hush. This was partly because, though the lectures were in public, no one reported on them, and their content would not be published by Harvey himself for another decade. But, given the College’s commitment to Galen, and its harsh treatment of anyone who failed to follow his principles, some sort of expression of shock might have been expected from his colleagues. There was none. There is not a single mention of the idea in the College Annals for the period, merely lengthy discussions about the chaotic publication of the Pharmacopoeia, the discovery of yet more ‘impure’ medicines during searches of the apothecaries’ shops, and arrangements for the College’s annual feast.

      This silence may have been because so few of the Fellows bothered to come to the lectures, or because so few understood them. More likely, it was because Harvey realized from the beginning the political as well as medical implications of his ideas. He did not at this stage spell them out, but they are evident in his discussions about the relative importance of the heart versus the brain.

      Despite references to bellows and cisterns, Harvey was emphatic that the heart was no mere mechanical pump. He kept to the principle that it was the body’s most important organ, the ‘source of all heat’, that the ‘vital spirits are manufactured in the heart’, invigorating the blood to keep the body alive.⁶⁶ However, when he came to his final lecture, the ‘banquet of the Brain’, he ran into difficulties sustaining this position. The cerebrum, he pronounced, was ‘the highest body in a very well-protected tower; hair, skin &c., as safeguards, so that nature [protects] no part more’. Having reached this conclusion, he paused for thought, as though realizing too late that he had compromised the primacy of the heart. This prompted the assertion that the brain was ‘not to be compared with the heart’. But he could not resist trying, provoking a Herculean struggle to reconcile the importance of one with the ingenuity of the other:

      The empire of the heart extends more widely in those [creatures] in which [there is] no brain. Perhaps more worthy than the heart, but the heart is necessarily prior … All animals have one most perfect part; man [has] this, excelling all the rest; and through this the rest are dominated; it is dominated by the stars wherefore the head [is] the most divine, and to swear by the СКАЧАТЬ