The Clockwork Universe: Isaac Newton, the Royal Society, and the Birth of the Modern World - Edward Dolnick (2011)

Part II. Hope and Monsters

Chapter 18. Flies as Big as a Lamb

The microscope came along a bit later than the telescope, but its discovery produced just as much amazement. Here, too, were new worlds, and this time teeming with life! The greatest explorer of these new kingdoms was an unlikely conquistador, a Dutch merchant named Antonie van Leeuwenhoek. He seems to have begun tinkering with lenses with no grander ambition than to check for defects in swatches of cloth.

Leeuwenhoek quickly moved beyond fabric samples. Peering through microscopes he built himself—more like magnifying glasses than what we think of as microscopes—he witnessed scenes that no one else had ever imagined. In a frenzy of excitement, he dashed off letters to the Royal Society, hundreds altogether, describing the “secret world” he had found. He thrilled at the living creatures in a drop of water scooped from a puddle and then found he did not even have to venture outdoors to find teeming, complex life. He put his own saliva under the microscope and “saw, with great wonder, that in the said matter there were many very little living animalcules, very prettily a-moving. The biggest sort had a very strong and swift motion, and shot through the spittle like a pike does through the water.”

Hooke had been experimenting with microscopes of his own design for years. Leeuwenhoek’s microscopes yielded clearer images, but on November 15, 1677, Hooke reported that he, too, had seen a great number of “exceedingly small animals” swimming in a drop of water. And he had witnesses. Hooke rattled off a list: “Mr. Henshaw, Sir Christopher Wren, Sir John Hoskyns, Sir Jonas Moore, Dr. Mapletoft, Mr. Hill, Dr. Croone, Dr. Grew, Mr. Aubrey, and diverse others.” The roll call of names highlights just how shocking these findings were. The microscope was so unfamiliar, and the prospect of a tiny, living, hitherto invisible world so astonishing, that even an eminent investigator like Hooke needed allies. It would be as if, in our day, Stephen Hawking turned a new sort of telescope to the heavens and saw UFOs flying in formation. Before he told the world, Hawking might coax other eminent figures to look for themselves.

But Hooke and the rest of the Royal Society could not catch Leeuwenhoek. Endlessly patient, omnivorously curious, and absurdly sharp-eyed, he racked up discovery after discovery.25 Sooner or later, everything—pond water, blood, plaque from his teeth—found its way to his microscope slides. Leeuwenhoek jumped up from his bed one night, “immediately after ejaculation before six beats of the pulse had intervened,” and raced to his microscope. There he became the first person ever to see sperm cells. “More than a thousand were moving about in an amount of material the size of a grain of sand,” he wrote in amazement, and “they were furnished with a thin tail, about five or six times as long as the body . . . and moved forward owing to the motion of their tails like that of a snake or an eel swimming in water.”26Leeuwenhoek hastened to assure the Royal Society that he had obtained his sample “after conjugal coitus” (rather than “by sinfully defiling myself”), but he did not discuss whether Mrs. Leeuwenhoek shared his fascination with scientific observation.

No matter. Others did. Even Charles II delighted in peering through microscopes and witnessing life in miniature. “His Majesty seeing the little animals, contemplated them in astonishment and mentioned my name with great respect,” Leeuwenhoek wrote proudly. This was a development almost as striking as Leeuwenhoek’s findings themselves. In the new world of science, a merchant who had never attended a university and knew only Dutch, not Latin, could make discoveries that commanded the attention of a king.

Both the microscope and the telescope fascinated the seventeenth century’s intelligentsia, not just its scientists. The telescope tended to produce unwelcome musings on man’s puniness, as we have seen, but the picture of worlds within worlds revealed by the microscope did not trouble most people. Pascal was an exception. The endless descent into microworlds—“limbs with joints, veins in these limbs, blood in these veins, humors in this blood, globules in these humors, gases in these globules”—left him queasy and afraid. Many a ten-year-old has delighted in an imaginary outward zoom that plays Pascal’s voyage in reverse: I live at 10 Glendale Road in the town of Marblehead in the county of Essex in the state of Massachusetts in the United States of America on the planet Earth in the Milky Way galaxy. Pascal’s inward journey shared the same rhythm, but the dread in his tone stood the child’s exhilaration on its head.

Most people felt more fascination than fright, perhaps simply because we tend to feel powerful in proportion to our size. In any case, both telescope and microscope strengthened the case for God as designer. The ordinary world had already provided countless examples of God’s craftsmanship. “Were men and beast made by fortuitous jumblings of atoms,” Newton wrote contemptuously, “there would be many parts useless in them—here a lump of flesh, there a member too much.” Now the microscope showed that God had done meticulous work even in secret realms that man had never known. Unlike those furniture makers, say, who lavished all their care on the front of their bureaus and desks but neglected surfaces destined to stay hidden, God had made every detail perfect.

The heavens declared the glory of God, and so did fleas and flies and feathers. Man-made objects looked shoddy in comparison. Hooke examined the tip of a needle under a microscope, to test the aptness of the expression “as sharp as a Needle.” He found not a perfect, polished surface but “large Hollows and Roughnesses, like those eaten in an Iron Bar by Rust and Length of Time.” A printed dot on the page of a book told the same story. To the naked eye it looked “perfectly black and round,” wrote Hooke, “but through the Magnifier it seemed grey, and quite irregular, like a great Splatch of London Dirt.”

No features of the natural world were too humble to inspire rapt study. In some of the earliest experiments with microscopes, Galileo had tinkered with various designs. His astonishment reaches us across a gap four centuries wide. Galileo had seen “flies which look as big as a lamb,” he told a French visitor, “and are covered all over with hair, and have very pointed nails by means of which they keep themselves up and walk on glass, although hanging feet upwards.”

Many of the objects that came in for close examination were even less grand than houseflies. In April 1669 Hooke and the other members of the Royal Society gazed intently at a bit of fat and then at a moldy smear of bookbinder’s paste, “which was found to have a fine moss growing on it.” One early scientist who studied plants under the microscope marveled that “one who walks about with the meanest stick holds a piece of nature’s handicraft which far surpasses the most elaborate . . . needlework in the world.”


Robert Hooke’s drawing of a fly’s meticulously “designed” eyes

Hooke published a lavish book called Micrographia that featured such stunning illustrations (by Hooke himself) as a twelve-by-eighteen-inch foldout engraving of a flea. The creature was, Hooke noted admiringly, “adorn’d with a curiously polish’d suit of sable Armour, neatly jointed.” Another oversize illustration showed a fly’s eyes, with some fourteen thousand facets or “pearls.” Hooke went out of his way to justify lavishing attention on so lowly an insect. “There may be as much curiosity of contrivance and structure in every one of these Pearls, as in the eye of a Whale or Elephant,” he wrote, and he noted that in any case God was surely up to such a task. “As one day and a thousand years are the same with him, so may one eye and ten thousand.”

Both telescope and microscope had opened up new worlds. The new vistas served to reinforce the belief that on every scale the universe was a flawless, harmonious, and unimaginably complex mechanism. God was a sculptor who could shape stars and planets and a craftsman with a delicacy of touch to shame the finest jeweler.