Sanctorius calculated that an eight-pound intake of meat and drink will, over one day, yield five pounds of insensible perspiration—or an average of three ounces of sweat and breath vapor lost per hour: three times the rate Macdougall observed. At one point Sanctorius describes the digestion of “a supper of eight pounds.”[14] It soon became clear there was little overlap between the dripping trencherman of Sanctorius’s day and Macdougall’s dry little consumptives. I skipped ahead to Section VI, which was all about the effects of immoderate coitus on insensible perspiration. Sanctorius effected the quaint habit of presenting his findings in the form of aphorisms. As in, “Aphorism XXXIX: Such a Motion of a Body as resembles that of a Dog in Coition, is more hurtful than a bare Emission of Semen; for the latter wearies only the internal Parts, but the other tires both the Bowels and the Nerves.” Or “Aphorism XL: To use Coition standing, after a Meal, is hurtful; because as it is upon a full Meal, it hinders the Offices of the Bowels.” Sanctorius preached that by obstructing insensible perspiration, immoderate sex led to everything from “Palpitations in the Eyebrows and Joynts” to a hardening of the tunicles of the eyes—and here we have what I surmise to be the original striking of the masturbation-makes-you-go-blind myth. Sanctorius preached a carnal moderation that seemed almost killjoy—all the more so for the book’s wanton promotion of oysters as sources “of the greatest possible nourishment.”
TO GET TO THE bottom of the insensible weight loss conundrum—is it an ounce per hour, as Macdougall calculated, or is it three?—I called America’s modern-day Sanctorius, Eric Ravussin. Ravussin, currently with the Pennington Biomedical Research Center in Baton Rouge, used to run metabolic chamber studies for the National Institutes of Health. He, too, has measured insensible water loss during sleep—by tucking volunteers into beds on platform scales inside the chamber. His findings came in right beside Macdougall’s: about an ounce per hour. Macdougall was right: It would be hard to imagine insensible water loss as the force behind an instantaneous drop of three-fourths of an ounce.
Ravussin had no idea what could have caused the abrupt weight loss. He referred me to a book by Max Kleiber, called The Fire of Life: An Introduction to Animal Energetics. Though a tad formula-heavy for the likes of me, the book is as diverting in spots as was Sanctorius’s. We learn, for instance, that the “extra-large vagina of the Brahman cow is an effective organ for heat dissipation.” In a similar vein, Schmidt-Nielsen “observed that a camel’s rectal temperature may rise during a day from 34.2 to 40.7 C,” though I doubt that, strictly speaking, observation alone did the trick. Sometimes you have to get right in there, as Kleiber himself did in 1945, calculating “the insensible weight loss of cows in pasture by preventing their water and food intake with a muzzle and collecting and weighing all feces and urine.” I skimmed the entire book, looking for some reference to a sudden weight drop at death. I found nothing. There is only so much one can do. In the words of Max Kleiber, “If we insisted on meeting all our fuel needs with eggs, we would soon reach the end.” Or something.
SO HOW ARE we to explain Macdougall’s befuddling finding? I have some theories for your consideration.
Theory the First: Duncan Macdougall was a nutter. I was an early supporter of the nutter theory, based largely on the fact that Macdougall was a member of the Massachusetts Homeopathic Medical Society. He wrote his medical school thesis on the Law of Similars, the underlying principle of homeopathy—basically Like Cures Like. I don’t know what homeopathists get up to nowadays, but back in the movement’s infancy it was nutter central. The homeopathists’ bible, A Dictionary of Practical Materia Medica, is a three-volume compendium of plants, animals, and minerals, and the symptoms they produce if you ingest them, which homeopathists did a lot of, perhaps accounting for the nutter situation. The central tenet was that substances that cause healthy people to get certain symptoms can cure diseases with these same symptoms. The early homeopathists spent years dosing themselves and their patients and friends with every substance they could get hold of, and carefully cataloguing the reported symptoms. I can’t vouch for the movement’s contributions to the healing arts—without control groups or placebos, the Materia work is meaningless by modern research standards—but I must commend their flair for language. For example, we have alumina causing “dreams of horses, of quarrels, of vexations” and a “tingling on the face, as if it were covered with a white of egg dried.” Agnus castus causes “odor before the nose, like herrings or musk,” as well as “feeble erections” and—it almost goes without saying—“great sadness.” And then there is chamomile, said to cause the symptom “cannot be civil to the doctor.”
But at the time Duncan Macdougall went to medical school, in 1893, homeopathy was not considered a fringe branch of medicine. About half the country’s medical schools—including Macdougall’s alma mater, Boston University—still taught the homeopathic approach to healing. (BU had dropped it by the early 1920s.) The point is, plenty of mainstream, straight-ahead physicians practiced homeopathy in Macdougall’s day.
Also working against the touchy-feely flake theory are the plentiful examples of Macdougall’s consistent toe-the-line geekdom. He was class president and class orator at BU. A 1907 article in the Boston Sunday Post flatly stated that Macdougall was a believer in neither spiritualism nor psychic phenomena. A Haverhill Evening Gazette piece described him as “hard-headed and practical.” Greg Laing, head of the History Room at the Haverhill Public Library, recalls visiting the Macdougall household with his parents as a boy, so I asked him about the good doctor’s nutter potential. (Macdougall had died by then, but his widow and son were still living.) “God, no,” said Laing. “They were such grim, straitlaced people. Really and truly, they were not esoterically inclined.” I phoned Olive Macdougall, the widow of Macdougall’s only grandchild. Though her husband never knew his grandfather, Olive confirmed the family’s decidedly nonmystical bent. Her father-in-law, Duncan’s son, was a banker and lawyer.
The writer of Duncan Macdougall’s Gazette obituary tried to foist a little jollity on the man, but it was a thin effort: “He was cheerful in the sickroom and some of his sickroom phrases and words of encouragement remain on the tongues of his patients. A few of his sickroom phrases were: ‘Don’t you worry, my gal, everything will be all right’ and ‘Don’t you worry and you’ll get well in a bigger hurry.’”
Macdougall was neither madman nor visionary. What he was, I’m guessing, was a henpecked little man in need of attention. Greg Laing described Macdougall’s wife Mary as “a battleaxe of monumental proportion.” (Perhaps a chamomile tea drinker.) “I don’t think she had the slightest respect or interest in her husband’s project.” Macdougall got his strokes from his work. As far as I can tell, he made a habit of calling up the local papers to garner laurels where he could. “Dr. Macdougall Becomes Poet,” overstates the headline when some limp doggerel ran in Life. “Dr. Macdougall Wins Great Fame,” blusters another, after England’s navy agreed to have its Royal Marine Bands play Macdougall’s lurching composition “The British Tar’s Song.” (Macdougall’s nephew had a contact at the Admiralty, whom he deluged with 1,800 copies of the song.)
14
Astoundingly, Sanctorius was described as a small man. His work habits may explain his ability to stay slim in an era of eight-pound dinners. He claimed to have tested ten thousand subjects over twenty-five years.