A Garden of Marvels Page 5
In 1653, when Hooke was eighteen, Busby managed to get him a place as a scholarship student at his former college, Christ Church, at Oxford. Hooke fell in with a circle of mathematically and scientifically minded young men who gathered around the warden of Wadham College, the charismatic Dr. John Wilkins. Wilkins was a tolerant man in grossly intolerant times, a man chiefly interested in finding and supporting others who he believed would advance the new “experimental philosophy” that animated certain Englishmen of the day. Hooke, as convinced as any of his new friends by the idea that nature must be “put to torture” to give up her secrets, was soon helping members of Wilkins’s circle run their investigations.
When Hooke finished at Christ Church, Wilkins helped him get a full-time position as an “operative” to Robert Boyle, a wealthy young Irish aristocrat who had dedicated himself to scientific research. Boyle was then embarking on a study of the physical properties, particularly the “springiness,” of air. That springiness, by which he meant compressed air’s tendency to rebound, he planned to investigate with an air pump, or what we would call a vacuum pump. Otto von Guericke had invented a primitive version about 1650, but Boyle needed a better one. It was Hooke who managed to construct the device with its pistons, cylinders, and valves coated in “Sallad Oyl” as a sealant, and who was the only one who could get the temperamental machine to work consistently. It was also Hooke who had the mathematics to turn the resulting data into “Boyle’s law,” which holds that there is an inverse relationship between pressure and the volume of gases. In short order, Hooke had become Boyle’s indispensable employee, as well as friend.
In 1660, a dozen scientifically minded gentlemen, including Boyle, Boyle’s close friend Christopher Wren, and others from Oxford, gathered in London to found an organization dedicated to the advancement of “Physico-Mathematicall Experimentall Learning.” The organization’s subjects of inquiry were to be “Physick, Anatomy, Geometry, Astronomy, Navigations, Staticks, Mechanicks, and natural Experiments”; its goal was to discover the laws governing the material world. Its members would consult only their experience, experiment, and observation. There was to be nothing of God or politics (and the membership was indeed a mix of Anglicans and dissenters, royalists and parliamentarians). The brash spirit of the enterprise was emblazoned on the Society’s coat of arms: Nullius in Verba, or “Take no man’s word for it.”
The monarchy was restored in May 1660, and in November Charles II chartered the organization, making it the Royal Society of London for Improving Natural Knowledge by Experiment, or more succinctly, the Royal Society. The Crown provided no financial support, but its royal charter gave it prestige and, better, the ability to publish without the standard government-granted license. That meant the group could disseminate information quickly and without censorship, a rare privilege at a time before governments acknowledged a right to a free press. The mathematician Viscount William Brouncker was elected president; Dr. Wilkins and Henry Oldenburg, a former German diplomat employed by Boyle as an amanuensis, were named co-secretaries. The Fellows, all gentlemen with independent incomes, would meet weekly. In November 1662, thanks to Boyle, Hooke was hired as Curator of Experiments, a position that required him to assist in four demonstrations of the Fellows’ experiments each week.
The early years of the Royal Society reflected the precarious state of scientific inquiry, teetering between a medieval worldview and modernity. The Fellows, more than a hundred strong, read their own papers, heard letters from some thirty foreign correspondents, hypothesized endlessly, and proposed research projects both sensible and bizarre. One of the founders, Sir Robert Moray, submitted a paper in which he discussed the shells he had seen in Scotland adhering to trees where, he said, they harbored little birds. Others reported that young vipers arose out of powdered viper livers and lungs, and that illnesses could be cured by magnetism. George Villiers, the second Duke of Buckingham, submitted what he contended was the horn of a unicorn. But Boyle, Wren, mathematicians Isaac Barrow and John Wallis (who gave us the googol), ichthyologist Francis Willoughby, the chemist Thomas Willis, naturalist John Ray, and many others were productive scientists.* Richard Lower, a physician, and Edmund King transfused blood between greyhounds, mastiffs, and sheep, and ultimately between a sheep and one young and very inebriated pub habitué. As a company, they witnessed Boyle’s gas experiments, Huygens’s pendulum experiments, and Mariotte’s investigations of the eye’s blind spot. Hoping that their work would have some practical and remunerative results—which was the king’s primary reason for chartering the organization—they also tested new brewing methods, compared the best soils and clays for brick-making, and investigated whether adding lime to soil would boost its fertility. Hooke took part in many of these experiments, as well as others involving carriages, fountains, clocks, lenses, chemicals, barometers, hygrometers, and magnets. The job required enormous energy, organizational ability, abstract knowledge, and mechanical skills, as well as considerable tact, given that every virtuoso, especially Boyle who employed him independently, considered his own work to be all-important. To their credit, everyone understood that Hooke was essential to the success of the Royal Society, and elected him a full member in June 1663 while continuing his salary.
Somehow, Hooke managed to find time for his own work. Since the mid-1650s, he and Wren had taken an interest in the microscope and what could be seen beneath its lenses. By 1661, Hooke had improved its design significantly by engineering a “scotoscope,” which consisted of an oil lamp, a glass globe filled with water, and a convex lens that concentrated and directed the lamplight onto a specimen.
He drew what he saw, and in March 1663, the Society entreated him to continue his microscopial observations and to demonstrate the views at the Society’s weekly meetings. One year later, it authorized publication of Hooke’s Micrographia, or Some Physiological Descriptions of Minute Bodies Made by Magnifying Glasses with Observations and Inquiries Thereupon.
From Micrographia, the microscope Robert Hooke used. Next to the instrument is Hooke’s scotoscope. The light of an oil lamp (K) passes through a water-filled globe (G). A lens (I) further concentrates light on the specimen.
The large-format book was a sensation for its detailed and beautifully executed illustrations of magnified specimens, ranging from a razor’s edge to a snowflake to a louse. Hooke was the first to show the world that a snail has teeth, a bee’s stinger has barbs at its tip, and a fly has “feathers” in the middle of its face. In a thin slice of cork, he saw it was composed of “little boxes or cells” (as in the cells of monks) without passageways between them. If Galileo lifted his readers to the stars, Hooke shrunk them to the size of a pinhead, turning a fly into a monster and a nettle leaf into a nightmarish landscape.
The illustrations were not what Hooke actually saw at the bottom of his microscope—the area of focus was too small for that—but were the sum of many partial views artfully crafted into a whole. Micrographia was utterly unprecedented, and revealed a new realm of nature that might be as vast and rich as the ordinary world. The perspective was entrancing but also deeply unsettling: No ancient and revered authority had ever mentioned the existence of such a realm. Today, we’re so accustomed to such sights, and those far more magnified, that it is hard to fully appreciate the shock and fascination of the drawings when they were first published. If a Mars Rover were to send back photographs of microscopic creatures we would be no less transfixed.
From Micrographia, the stinging nettle with sacs of fluid at the base of its needles.
The book was a huge success, print runs sold out repeatedly, and the finances of the straitened Society benefited considerably. Pepys bought a copy immediately on its release and stayed up until two o’clock in the morning reading it, declaring it “the most ingenious book that I ever read in my life.” Other London gentlemen, Pepys noted in his diary, rushed out to buy their own microscopes so they could go “microscoping” and see the wonders for themselves.*
F
or the most part, Hooke was happy to be a tourist of the microscopic world, sending home the most marvelous picture postcards and writing detailed, lively descriptions of exactly how everything looked. Despite his deep understanding of the elaborate mechanisms of machines, he did not try to take apart the insects and plants he viewed. He called himself a “mechanical philosopher” and his greatest love was for the way the inanimate world worked. Chemistry and combustion interested him, and he would invent a clock, the sash window, the universal joint; write a book about comets; and become a surveyor and an architect, while continuing, for forty-one years, to demonstrate experiments at the Society. With Wren he would design most of the major Royal and City buildings after the Great Fire of London in 1666. But he didn’t think to use his microscope to look inside his living specimens—the louse, the fly, and the nettle—to see what internal structures they had or how they operated. Instead, he spoke of an anima in plants, a kind of spirit that makes them “useful to the great work or function they are to perform.” Aristotle would have said as much.
But if Hooke didn’t think to explore the inside of plants, others did.
four
The Persecuted Professor
It is late January in the year 1672, and Marcello Malpighi, forty-three-year-old professor of practical medicine, is sitting in the front row of the anatomy amphitheater at the University of Bologna, attending what is known as the public anatomy lesson. Below him, on the white marble slab at the center of the room, is a human body, gleaming red and partially eviscerated. A man in a bloody coat stands at the side of the slab. He is the dissector, and after excavating an organ he holds it up, turning around to exhibit it to the audience. The lecturer, a medical professor in a black gown and fur collar, stands at the far end of the amphitheater in the cathedra, an elevated and canopied pulpit, and reads from one of the texts of Galen, the great Roman physican, to explain to the audience what it is seeing. There are many other professors in the room, and they pepper the lecturer with questions and objections. But Malpighi, the world’s most knowledgeable anatomist, has said nothing since the proceedings began. His dark eyes are impassive, his pale face framed by shoulder-length black hair and sectioned by a narrow black mustache and a vertical line of beard. From time to time, he takes notes, not on the bloody organs that the dissector raises, but on the other professors’ comments.
This year’s dissection is drawing an even larger crowd than usual: The subject is a woman just postpartum, quite a rarity. The amphitheater, the pride of Bologna and the university, is designed for drama. The wooden ceiling is deeply coffered and ornate with carved medallions, rosettes, and Latin-inscribed scrolls. At its recessed center, a languid Apollo hovers over the proceedings below. The walls, hung with red damask for the occasion, have deep niches that shelter life-sized statues of twelve classical philosophers and busts of renowned Bolognese medical professors. Candles in wall sconces weakly illuminate the room. Wax torches at the head and feet of the cadaver cast a fiercer light.
Around the railing that encircles the slab, medical students crowd three-deep. Behind them, benches that look like choir stalls rise steeply in rows. Government officials in full scarlet robes are seated at the far end of the amphitheater. The cardinal legate—Bologna is a papal state—is dressed in lace, a red skullcap, and red stole and university officials in black gowns occupy the seats nearest the lecturer. Students, professors, clergymen, gentlemen and ladies in their rich green, yellow, and rose silks with full sleeves and broad lace collars, and members of the ordinary public, many of them rowdy masqueraders disguised in the elaborate costumes of Carnival, cram the remaining seats on the two longer sides. In fact, the public anatomy is timed to coincide with the holiday, so as many people as possible, including foreigners who arrive especially for the event, can be dazzled by the building, impressed by the intellectual caliber of the university, possibly educated, and certainly entertained.
Corpses for the anatomy lesson are often hard to come by. Regulations prohibit the use of the body of anyone who had resided within thirty miles of the city. Sometimes a public execution is delayed to provide a fresh subject, and occasionally a doomed convict benefits by having his sentence reduced from a protracted drawing-and-quartering, which produces a cadaver unsuited for teaching, to a quicker hanging. However, at least one unfortunate has had his sentence changed from life imprisonment to hanging to accommodate the annual event. (Lest you think these Bolognese are heartless, the anatomy professor pays for masses to be said for the departed soul.) In any event, the scarcity of cadavers means one has to last for as long as two weeks. Fortunately, Bologna is cold in mid-winter. The intestines and stomach, the organs most likely to stink, are always the first to be removed and dissected. Still, by the end of the session the smells can be as vivid as the sights.
Professor Malpighi isn’t bothered by the odors. In fact, this particular corpse and some of its organs will soon find their way to his house in town, where he and select students will continue to scrutinize them. They will inspect the intricate structure of the veins, arteries, and nerves of the ovaries and the connections between the uterus and the remains of the placenta. Painstaking, microscopic dissections undertaken privately have been Malpighi’s preoccupation for ten years. Whatever time he can spare from teaching and tending to patients, he spends in his home laboratory. Although he continues to attend the public sessions—it would be grossly impolitic not to—it is no secret that he finds them ridiculous. How can a lecturer reading from Galen about organs that a butcher of a dissector has wrenched from a body teach anything meaningful? It is not unusual for a dissector to be holding up one organ while the lecturer, standing half the length of the room away, is reading about another. For Malpighi, the public anatomies, like his medical practice, are disagreeable necessities, distractions from his real work.
This particular session is worse than a waste of his time. The lecturer suffering in the cathedra, Giovanni Carlo Lanzi Paltroni, is his friend and former student and now a faculty member. Until now, Paltroni had been able to avoid a turn in the rotuli, the annual rotation of anatomy professors who lecture publicly. The cost of taking on the lecture series—in addition to paying for masses for the deceased, a first-time lecturer has to buy expensive gifts for officials and students—has been a disincentive. But worse has been the prospect of the disputatio, the verbal thrust-and-parry phase between the lecturer and other professors and students, which is a highlight of the event. The government officials in attendance determine the lecturer’s salary, and his performance will weigh heavily in their calculations. Paltroni has feared, with good reason, an all-out attack by a powerful group of the university’s most prominent medical professors, including Professors Giovanni Sbaraglia and Paolo Mini.
Paltroni’s problem is his friendship with Malpighi. Malpighi is a mild-mannered and courteous if rather gloomy man, a conscientious mentor to his medical students, and an artist and connoisseur of Italian painting. Nonetheless, he is despised by most of his colleagues. The Bologna medical faculty members are archconservatives in the world of medicine, strict adherents of the ancient Greek and Arab medicine that the Catholic Church supports. Recently, they have established a new rule: All new medical professors must swear to the doctrines of Aristotle, Hippocrates, and Galen, and “never allow their principles and conclusions to be overturned or destroyed by anyone.” One writer who is decidedly not on the curriculum is Vesalius, the sixteenth-century Belgian physician and anatomist who exposed more than two hundred errors in Galen’s treatises.* The purpose of the autopsy, from the “obscurantists’ ” point of view, is not to discover new information, but to demonstrate the accuracy of ancient knowledge. Any disparities between Galen’s description of human organs and what one can actually see under the glare of the torches can only be apparent differences, differences that the lecturer is bound to resolve in Galen’s favor.
Malpighi’s zeal for anatomy arouses suspicion among many of his fellow professors. To his opponents this
intensive exploration of the body’s organs is a repudiation of the ancients’ work. Illness, according to Hippocrates and affirmed by Galen, is caused by an excess or deficiency of one or more of the four “humors”: blood, phlegm, yellow bile, and black bile. To balance the humors, medical treatments involve bloodletting and drugs (usually plant-based) that induce vomiting, diarrhea, urination, and sweating. Other treatments work by offsetting the symptoms of an excess or deficiency of a humor, like drinking “cooling asses’ milk” to counter fever brought on by overheated blood.
Another strike against Malpighi is that he relies on a microscope—a small, upright model created by Italian instrument maker Divini—in his work of prising apart organs and tissues. In one, typical, six-month period, Malpighi wrote up and illustrated minute dissections of pregnant and nongravid cows; two girls, one a pregnant eighteen-year-old and the other a nineteen-year-old virgin; the penile glands of a dog; the gallbladder and bile ducts of a snake; the fleshy fibers in a ray’s gills and a spiral valve in its intestines; the uterus and spleen of a dogfish; the skin on a dog’s pads; a squid; the reproductive organs, liver, and kidneys of a mouse; the eye of a cow; the tongue of a horse; the skin of a human hand; and the paws of a mole. Little escapes his scalpel. Several of his discoveries will be immortalized in modern medical terminology, including the malpighian layer of skin and the malpighian bodies of the kidney. His most notable microscopial discovery, however, is the existence of capillaries, the minute blood vessels connecting arteries that carry blood from the heart to veins that return it. Capillaries are the missing links, literal and figurative, that clinch William Harvey’s theory that blood circulates, and is not, as Galen believed, used up in the body as food. Malpighi’s detailed reports, thoroughly illustrated, on the microstructure of human lungs, tongue, brain, skin, and many other organs have been published in Latin in Italy between 1661 and 1667.