At Home: A Short History of Private Life

by Bill Bryson

Most cities suffered devastating fires from time to time; some had them repeatedly. Boston had them in 1653, 1676, 1679, 1711, and 1761. Then it had a lull until the winter of 1834, when a fire in the night burned down seven hundred buildings—most of the downtown—and grew so fierce that it spread to ships in the harbor. But all city fires pale when compared with the fire that swept through Chicago on a windy night in October 1871, when a cow owned by a Mrs. Patrick O’Leary reputedly kicked over a kerosene lantern in a milking shed on DeKoven Street, and all kinds of dreadful mayhem swiftly followed. The fire destroyed 18,000 buildings and made 150,000 people homeless. Damages topped $200 million and put fifty-one insurance companies out of business. The following year, Boston had another big fire, which destroyed nearly 800 buildings and left 60 acres of smoldering waste.

One natural phenomenon promised to eliminate all the foregoing dangers and shortcomings: electricity. Electricity was exciting stuff, but it was hard to devise practical applications for it. Using the legs of frogs and electricity from simple batteries, the eighteenth-century Italian physician and physicist Luigi Galvani showed how electricity could make muscles twitch. His nephew, Giovanni Aldini, realizing that money could be made from this, devised a stage show in which he applied electricity to animate the bodies of recently executed murderers and the heads of guillotine victims, causing their eyes to open and their mouths to make noiseless shapes. The logical assumption was that if electricity could stir the dead, imagine how it might help the living. In small doses (at least we may hope they were small), it was used for all kinds of maladies, from treating constipation to stopping young men having illicit erections (or at least enjoying them). Charles Darwin, driven to desperation by a mysterious lifelong malady that left him chronically lethargic, routinely draped himself with electrified zinc chains, doused his body with vinegar, and glumly underwent hours of pointless tingling in the hope that it would effect some improvement. It never did.

The real need was for a practical electric light. In 1846, rather out of the blue, a man named Frederick Hale Holmes patented an electric arc lamp. Holmes’s light was made by generating a strong electric current and forcing it to jump between two carbon rods—a trick that the British chemist Sir Humphry Davy had demonstrated but not capitalized on more than forty years earlier. In Holmes’s hands the result was a blindingly bright light. Almost nothing is known about Holmes—where he came from, what his educational background was, how he learned to master electricity. All that is known is that he worked at the École Militaire in Brussels, where he developed the concept with a Professor Floris Nollet, then returned to England and brought his invention to the great Michael Faraday, who saw at once that it could provide a perfect light for lighthouses.

The principle of incandescent lighting had been understood, and in fact conquered, for a surprisingly long time. As early as 1840, seven years before Thomas Edison was even born, Sir William Grove, a lawyer and judge who was also a brilliant amateur scientist with a particular interest in electricity, demonstrated an incandescent lamp that worked for several hours, but nobody wanted a lightbulb that cost a lot to make and only worked for a few hours, so Grove didn’t pursue its development. In Newcastle, a young pharmacist and keen inventor named Joseph Swan saw a demonstration of Grove’s light and made some successful experiments of his own, but the technology was lacking to get a really good vacuum in a bulb. Without that vacuum, any filament would burn out quickly, making a bulb a costly, short-lived indulgence.

Then in the early 1870s, Hermann Sprengel, a German chemist working in London, invented a device that came to be called the Sprengel mercury pump. This was the crucial invention that actually made household illumination possible. Unfortunately, only one person in history thought Hermann Sprengel deserved to be better known: Hermann Sprengel. Sprengel’s pump could reduce the amount of air in a glass chamber to one-millionth of its normal volume, which would enable a filament to glow for hundreds of hours. All that was necessary now was to find a suitable material for the filament.

The most determined and well-promoted search was undertaken by Thomas Edison, America’s premier inventor. By 1877, when he started his quest to make a commercially successful light, Edison was already well on his way to becoming known as “the Wizard of Menlo Park.” Edison was not a wholly attractive human being. He didn’t scruple to cheat or lie, and was prepared to steal patents or bribe journalists for favorable coverage. In the words of one of his contemporaries, he had “a vacuum where his conscience ought to be.” But he was enterprising and hardworking and a peerless organizer.

On the last day of 1879, Edison invited a select audience to come and witness a demonstration of his new incandescent lights. As they arrived at his estate at Menlo Park, New Jersey, they were wowed by the sight of two buildings warmly aglow. What they didn’t realize was that the light was mostly non-electrical. Edison’s overworked glass blowers had been able to prepare only thirty-four bulbs, so the bulk of the illumination actually came from carefully positioned oil lamps.

However, when Edison’s first practical installation did come, it was far more prominent and therefore more lastingly significant. Edison wired a whole district of lower Manhattan, around Wall Street, to be powered by a plant installed in two semiderelict buildings on Pearl Street. Through the winter, spring, and summer of 1881–82, Edison laid fifteen miles of cable and fanatically tested and retested his system. Not all went smoothly. Horses behaved skittishly in the vicinity until it was realized that leaking electricity was making their horseshoes tingle. Back at Edison’s workshops, several of his men lost teeth to mercury poisoning from overexposure to Sprengel’s mercury pump. But all the problems were finally resolved, and on the afternoon of September 4, 1882, Edison, standing in the office of the financier John Pierpont (J. P.) Morgan, threw a switch that illuminated eight hundred electric bulbs in the eighty-five businesses that had signed up for his scheme. Where Edison truly excelled was as an organizer of systems. The lightbulb was a wondrous thing but of not much practical use when no one had a socket to plug it into. Edison and his tireless workers had to design and build the entire system from scratch, from power stations to cheap and reliable wiring, to lamp stands and switches. Within months, Edison had set up no fewer than 334 small electrical plants all over the world; within a year or so, his plants were powering thirteen thousand lightbulbs. Cannily, he ...

As electricity became more freely available, many people found it unnerving to be relying for comfort on an invisible force that could swiftly and silently kill. Most electricians were hastily trained and all were necessarily inexperienced, so the profession quickly became one for daredevils. Newspapers gave full and vivid accounts whenever an electrician electrocuted himself, as happened pretty routinely. In England, the poet Hilaire Belloc offered a snatch of doggerel that caught the public mood: Some random touch—a hand’s imprudent slip— The Terminals—flash—a sound like “Zip!” A smell of burning fills the startled Air— The Electrician is no longer there!

In 1896, Edison’s former partner Franklin Pope electrocuted himself while working on the wiring in his own house, proving to many people’s satisfaction that electricity was too dangerous even for experts. Fires due to electrical faults were not uncommon. Lightbulbs sometimes exploded, always startlingly, sometimes disastrously. The new Dreamland Park at Coney Island burned down in 1911 after a lightbulb burst. Errant sparks from faulty connections caused more than a few gas mains to explode, which meant that one didn’t even have to be connected to the electricity supply to be perilously at risk.

ineluctably followed:

It is right to give Thomas Edison the credit for much of this, so long as we remember that his genius was not in creating electric light, but in creating methods of producing and supplying it on a grand commercial scale, which was actually a much larger and far more challenging ambition. It was also a vastly more lucrative one.

If you had to summarize it in a sentence, you could say that the history of private life is a history of getting comfortable slowly. Until the eighteenth century, the idea of having comfort at home was so unfamiliar that no word existed for the condition. Comfortable meant merely “capable of being consoled.” Comfort was something you gave to the wounded or distressed. The first person to use the word in its modern sense was the writer Horace Walpole, who remarked in a letter to a friend in 1770 that a certain Mrs. White was looking after him well and making him “as comfortable as is possible.”

Nowhere in the house is the spirit (if not always the actuality) of comfort better captured than in the curiously named room in which we find ourselves now, the drawing room. The term is a shortening of the much older withdrawing room, meaning a space where the family could withdraw from the rest of the household for greater privacy, and it has never settled altogether comfortably into widespread English usage.

For a time in the seventeenth and eighteenth centuries, drawing room was challenged in more refined circles by the French salon, which was sometimes anglicized to saloon, but both those words gradually became associated with spaces outside the home, so that saloon came first to signify a room for socializing in a hotel or on a ship, then a place for dedicated drinking, and finally, and a little unexpectedly, a type of automobile. Salon, meanwhile, became indelibly attached to places associated with artistic endeavors before being appropriated (from about 1910) by providers of hair care and beauty treatments. Parlor, the word long favored by Americans for the main room of the home, has a kind of nineteenth-century frontier feel to it, but in fact is the oldest word of all. It was first used in 1225, referring to a room where monks could go to talk (it is from the French parler, “to speak”), and was extended to secular contexts by the last quarter of the following century.

Drawing room is the name used by Edward Tull on his floorplan of the Old Rectory, and almost certainly is the term employed by the well-bred Mr. Marsham, though he was probably in a minority even then. By midcentury it was being supplanted in all but the most genteel circles by sitting room, a term first appearing in English in 1806. A later challenger was lounge, which originally signified a type of chair or sofa, then a jacket for relaxing in, and finally, from 1881, a room. In America...

Though the drawing room became the focus of comfort in the home, the story doesn’t actually start there; it doesn’t start in the house at all. It starts outdoors, a century or so before Mr. Marsham’s birth, with a simple discovery that would make landed families like his very rich and allow him one day to build himself a handsome rectory. The discovery was merely this: land didn’t have to be rested regularly to retain its fertility. It was not the most staggering of insights, but it changed the world. Traditionally, most English farmland was divided into long strips called furlongs and each furlong was left fallow for one season in every three—sometimes one season in two—so that it could recover its ability to produce healthy crops.* This meant that in any given year at least one-third of the nation’s farmland stood idle. In consequence, there wasn’t sufficient feed to keep large numbers of animals alive through the winter, so landowners had no choice but to slaughter most of their stock each autumn and face a long, lean period till spring. Then English farmers discovered something that Dutch farmers had known for a long time: if turnips, clover, or one or two other amenable crops were sown on the idle fields, they miraculously refreshed the soil and produced a bounty of winter fodder into the bargain. It was the infusion of nitrogen that did it, though no one would understand that for nearly two hundred years. What was understood, and very much appreciated, was that crop ...

Farmers also benefited from a new wheeled contraption invented in about 1700 by Jethro Tull, a farmer and agricultural thinker in Berkshire. Called a seed drill, it allowed seeds to be planted directly into the soil rather than broadcast by hand. Seed was expensive, and Tull’s new drill reduced the amount needed from three or four bushels per acre to under one; and because the seeds were planted at even depths in neat rows, more of them sprouted successfully, so yields improved dramatically, too, from between twenty and forty bushels an acre to as much as eighty.

gratifying heaps of lucre.

The Duke of Bridgewater earned annual returns of 40 percent—and really returns don’t get much better than that—from a canal monopoly in the North of England. All of this was in an age in which there was no income tax, no capital gains tax, no tax on dividends or interest—almost nothing to disturb the steady flow of money being banked. Many people were born into a world in which they had to do virtually nothing with their wealth but stack it. The third Earl of Burlington, to take one example of many, owned vast estates in Ireland—some forty-two thousand acres in all—and never visited the country. Eventually he was made lord treasurer of Ireland and still never visited it.

This was unfortunate, as the Marlboroughs were notoriously parsimonious. The duke was so cheap that he refused to dot his i’s when he wrote, to save on ink.

Whatever one thought of Vanbrugh and his creations, the age of the celebrity architect had begun.* Before Vanbrugh’s day, architects weren’t much celebrated. Generally, fame went to those who paid for the houses, not those who designed them. Hardwick Hall, which we encountered in Chapter III, was one of the great buildings of its age, yet it is merely supposed that Robert Smythson was the architect. It is a pretty good supposition, for all kinds of reasons, but there is no actual proof of it. Smythson was in fact the first man to be called an architect—or nearly to be called an architect—on a monument of about 1588, in which he is described as “architector and survayor.” But as with so many others of his era, very little is known about his early life, including where he was born and when. He makes his first appearance in the records at Longleat House at Wiltshire in 1568, when he was already in his thirties and a master mason. Where he was before that is completely unknown. Even after architecture became a recognized profession, most practitioners came from other backgrounds. Inigo Jones was a designer of theatrical productions, Christopher Wren an astronomer, Robert Hooke a scientist, Vanbrugh a soldier and playwright, William Kent a painter and interior designer. As a formal profession, architecture was actually very late developing. Compulsory examinations were not introduced until 1882 in Britain, and architecture wasn’t offered anywhere as a full-time academic discipl...

The one thing all buildings had in common through Adam’s day was a rigorous devotion to symmetry. Vanbrugh, to be sure, didn’t entirely achieve symmetry at Castle Howard, but that was largely accidental. Elsewhere, however, symmetry was adhered to as an immutable law of design. Every wing had to have a matching wing, whether it was needed or not, and every window and pediment to one side of the main entrance had to be exactly mirrored by windows and pediments on the other side regardless of what went on behind them. The result often was the building of wings that no one really wanted. Not until the nineteenth century did this absurdity begin to end,

In 1784, Beckford became the centerpiece of the most spectacularly juicy scandal of his age when it emerged that he was involved in a pair of tempestuous, wildly dangerous dalliances.

Those homely attributes would be the creation of a new type of person who had scarcely existed a generation or so before: the middle class professional. There had always been people of middling rank, of course, but as a distinct entity and force to be reckoned with, the middle class was an eighteenth-century phenomenon. The term middle class wasn’t coined until 1745 (in a book on the Irish wool trade, of all things), but from that point onward the streets and coffeehouses of Britain abounded with confident, voluble, well-to-do people who answered to that description: bankers, lawyers, artists, publishers, designers, merchants, property developers, and others of generally creative spirit and high ambition. This new and swelling middle class served not only the very wealthy but also, even more lucratively, one another. This was the change that made the modern world.

The growth of empire and of overseas business interests had a dramatic effect, too, often in unexpected ways. Take wood. When Britain was an isolated island nation, it had essentially just one wood for furniture making: oak. Oak is a noble material, solid, long-lasting, literally hard as iron, but it is really only suitable for dense, blocky furniture—trunks, beds, heavy tables, and the like. But the development of the British navy and the spread of Britain’s commercial interests meant that woods of many types—walnut from Virginia, tulipwood from the Carolinas, teak from Asia—became available, and these changed everything within the home, including how people sat and conversed and entertained.

Mahogany would have been nothing like as esteemed a wood as it was had it not been for one other magical new material, from the other side of the Earth, that gave it the most splendid finish: shellac. Shellac is a hard resinous secretion from the Indian lac beetle. Lac beetles emerge in swarms in parts of India at certain times of the year, and their secretions make varnish that is odorless, nontoxic, brilliantly shiny, and highly resistant to scratches and fading. It doesn’t attract dust while wet, and it dries in minutes. Even now, in an age of chemistry, shellac has scores of applications against which synthetic products cannot compete. When you go bowling, it is shellac that gives the alleys their peerless sheen, for instance.

Thomas Chippendale made indisputably fine furniture, but so did lots of others. St. Martin’s Lane alone had thirty furniture makers in the eighteenth century, and hundreds more were scattered across London and throughout the country. The reason we all know Chippendale’s name today is that in 1754 he did something quite audacious. He issued a book of designs called The Gentleman and Cabinet-Maker’s Director, containing 160 plates. Architects had been doing this sort of thing for nearly two hundred years, but nobody had thought to do it for furniture. The drawings were unexpectedly beguiling. Instead of being flat, two-dimensional templates, as was standard, they were perspective drawings, full of shadow and sheen. The prospective purchaser could immediately visualize how these handsome and desirable objects would look in his own home. It would be misleading to call Chippendale’s book a sensation, because only 308 copies were sold, but the purchasers included forty-nine members of the aristocracy, which made it disproportionately influential. It was also snapped up by other furniture makers and craftsmen, raising another point of oddness—that Chippendale was openly inviting his competitors to make use of his designs for their own commercial purposes. This helped ensure Chippendale’s posterity, but didn’t do much for his immediate fortunes since potential clients could now get Chippendale furniture made more cheaply by any reasonably skilled joiner. It also meant two centurie...

As furniture makers, Chippendale and his contemporaries were masters without any doubt, but they enjoyed one special advantage that can never be replicated: the use of the finest furniture wood that has ever existed, a species of mahogany called Swietenia mahogani. Found only on parts of Cuba and Hispaniola (the island today shared by Haiti and the Dominican Republic) in the Caribbean, Swietenia mahogani has never been matched for richness, elegance, and utility. Such was the demand for it that it was entirely used up—irremediably extinct—within just fifty years of its discovery. Some two hundred other species of mahogany exist in the world, and most are very good woods, but they have nothing like the richness and smooth workability of the departed S. mahogani. The world may one day produce better chairmakers than Chippendale and his peers, but it will never produce finer chairs.

If we were to go back in time to a house in Chippendale’s day, one difference that would immediately strike us would be that chairs and other items of furniture were generally pushed up against the walls, giving every room the aspect of a waiting room. Chairs or tables in the middle of the room would have looked as out of place to Georgians as a wardrobe left in the middle of a room would look to us today. (One reason for pushing them aside was to make it easier to walk through rooms without tripping over furniture in the dark.) Because they were kept against the wall, the backs of early upholstered chairs and settees were often left unfinished, just as we leave bare the backs of chests and wardrobes today. When one had visitors, the custom was to bring an appropriate number of chairs forward and arrange them in a circle or semicircle, rather like storytime in an elementary school. This had the inevitable effect of making nearly all conversations strained and artificial. Horace Walpole, after sitting for four and a half hours in an agonizing circle of fatuous conversation, declared: “We wore out the Wind and the Weather, the Opera and the Play … and every topic that would do in a formal circle.” Yet when daring hostesses tried to introduce spontaneity by arranging chairs into more intimate clusters of threes and fours, many felt the result was tantamount to pandemonium, and more than a few could never get used to the idea of conversations taking place behind their backs.

The one problem with the chairs of the age was that they weren’t terribly comfortable. The obvious solution was to pad them, but that proved more difficult than one might have thought, because few craftsmen had all the skills necessary to make a good padded chair. Manufacturers struggled to get square edges where fabric met wood—piping and cording were originally brought in as a way of disguising these inadequacies—and were frequently out of their depth at producing padding that would maintain a permanent domed shape on the seat. Only saddlers could reliably provide the requisite durability, which is why so much early upholstered furniture was covered in leather. Fabric upholsterers also had the problem that many preindustrial fabrics could be produced only in widths of about twenty inches, creating a need for seams in awkward places. Only after the invention of the flying shuttle by John Kay in 1733 did it become possible to produce fabrics in widths of three feet or so.

The upshot is that, by late in the eighteenth century, households were full of features that would have been the wildest indulgences a century before. The modern house—a house such as we would recognize today—had begun to emerge. At last, some fourteen hundred years after the Romans withdrew, taking their hot baths, padded sofas, and central heating with them, the British were rediscovering the novel condition of being congenially situated.

We know almost nothing about how Mr. Marsham used this room, not simply because we know so little about Mr. Marsham but also because we know surprisingly little about certain aspects of dining rooms themselves. In the middle of the table was likely to have stood an object of costly elegance known as an epergne (pronounced “ay-pairn”), consisting of dishes connected by ornamental branches, each dish containing a selection of fruits or nuts. For a century or so, no table of discernment was without its epergne, but why it was called an epergne no one remotely knows. The word doesn’t exist in French. It just seems to have popped into being from nowhere.

Around the epergne on Mr. Marsham’s table are likely to have been cruet stands—elegant little racks, usually of silver, holding condiments—and these, too, have a mystery. Traditional cruet stands came with two glass bottles with stoppers, for oil and vinegar, and three matching casters—that is, bottles with perforated tops for sprinkling (or casting) flavorings onto food. Two of the casters contained salt and pepper, but what went into the third caster is unknown. It is generally presumed to have been dried mustard, but that is really because no one can think of anything more likely. “No satisfactory alternative has ever been suggested” is how the food historian Gerard Brett has put it.

Why it is that these two, out of all the hundreds of spices and flavorings available, have such a durable venerability is one of the questions with which we began the book. The answer is a complicated, dramatic one. I can tell you at once that nothing you touch today will have more bloodshed, suffering, and woe attached to it than the innocuous twin pillars of your salt and pepper set.

Salt is a cherished part of our diet for a very fundamental reason. We need it. We would die without it. It is one of about forty tiny specks of incidental matter—odds and ends from the chemical world—that we must get into our bodies to give ourselves the necessary zip and balance to sustain daily life. Collectively, those specks are known as vitamins and minerals, and there is a great deal—a really quite surprising amount—that we don’t know about them, including how many of them we need, what exactly some of them do, and in what amounts they are optimally consumed.

That they were needed at all was a piece of knowledge that was an amazingly long time coming. Until well into the nineteenth century, the notion of a well-balanced diet had occurred to no one. All food was believed to contain a single vague but sustaining substance—“the universal aliment.” A pound of beef had the same value for the body as a pound of apples or parsnips or anything else, and all that was required of a human was to make sure that an ample amount was taken in. The idea that embedded within particular foods were vital elements that were central to one’s well-being had not yet been thought of. That’s not altogether surprising, because the symptoms of dietary deficiency—lethargy, aching joints, increased susceptibility to infection, blurred vision—seldom suggest dietary imbalance. Even today if your hair started to fall out or your ankles swelled alarmingly, it is unlikely yo...

Of scurvy alone it has been suggested that as many as two million sailors died between 1500 and 1850. Typically, scurvy killed about half the crew on any long voyage. Various desperate expedients were tried. Vasco da Gama on a cruise to India and back encouraged his men to rinse their mouths with urine, which did nothing for their scurvy and can’t have done much for their spirits either. Sometimes the toll was truly shocking. On a three-year voyage in the 1740s, a British naval expedition under the command of Commodore George...

Over time, people noticed that sailors with scurvy tended to recover when they got to a port and received fresh foods, but nobody could agree what it was about those foods that helped them. Some thought it wasn’t the foods at all, but just a change of air. In any case, it wasn’t possible to keep foods fresh on long voyages, so simply identifying efficacious vegetables and the like was slightly pointless. What was needed was some kind of distilled essence—an antiscorbutic, as the medical men termed it—that would be effective against scurvy but portable, too. In the 1760s, a Scottish doctor named William Stark, evidently encouraged by Benjamin Franklin, conducted a series of patently foolhardy experiments in which he tried to identify the active agent by, somewhat bizarrely, depriving himself of it. For weeks he lived...

In roughly the same period, James Lind, a naval surgeon, conducted a more scientifically rigorous (and personally less risky) experiment by finding twelve sailors who had scurvy already, dividing them into pairs, and giving each pair a different putative elixir—vinegar to one, garlic and mustard to another, oranges and lemons to a third, and so on. Five of the groups showed no improvement, but the pair given oranges and lemons made a swift and total recovery. Amazingly, Lind decided to ignore the significance of the res...

It fell to the great Captain James Cook to get matters onto the right course. On his circumnavigation of the globe in 1768–71, Captain Cook packed a range of antiscorbutics to experiment on, including thirty gallons of carrot marmalade and a hundred pounds of sauerkraut for every crew member. Not one person died from scurvy on his voyage—a miracle that made him as much a national hero as his discovery of Australia or any of his other many achievements on that epic undertaking. The Royal Society, Britain’s premier scientific institution, was so impressed that it awarded him the Copley Medal, its highest distinction. The British navy itself was not...

The realization that an inadequate diet caused not only scurvy but a range of common diseases was remarkably slow to become established. Not until 1897 did a Dutch physician named Christiaan Eijkman, working in Java, notice that people who ate whole-grain rice didn’t get beriberi, a debilitating nerve disease, while people who ate polished rice very often did. Clearly some thing or things were present in some foods, and missing in others, and served as a determinant of well-being. It was the beginning of an understanding of “deficiency disease,” as it was known, and it won Eijkman the Nobel Prize in medicine even though he had no idea what these active agents were. The real breakthrough came in 1912, when Casimir Funk, a Polish biochemist working at the Lister Institute in London, isolated thiamine, or vitamin B1, as it is now more generally known. Realizing it was part of a family of molecules, he combined the terms vital and amines to make the new word vitamines. Alth...

Meanwhile, it turned out that Funk’s vitamines were not nearly as coherent a group as originally thought. Vitamin B proved to be not one vitamin but several, which is why we have B1, B2, and so on. To add to the confusion, vitamin K has nothing to do with an alphabetical sequence. It was called K because its Danish discoverer, Henrik Dam, dubbed it Koagulations vitamin for its role in blood clotting. Later, folic acid (sometimes called vitamin B9) was added to the group. Two other vitamins—pantothenic acid and biotin—don’t have numbers or, come to that, much profile, but that is largely because they almost never cause us problems. No human has yet been found with insufficient quantities of either.

Vitamins are curious things. It is odd, to begin with, that we cannot produce them ourselves when we are so very dependent on them for our well-being. If a potato can produce vitamin C, why can’t we? Within the animal kingdom only humans and guinea pigs are unable to synthesize vitamin C in their own bodies. Why us and guinea pigs? No point asking. Nobody knows. The other remarkable thing about vitamins is the striking disproportion between dosage and effect. Put simply, we need vitamins a lot, but we don’t need a lot of them. Three ounces of vitamin A, lightly but evenly distributed, will keep you purring for a lifetime. Your B1 requirement is even less—just one ounce spread over seventy or eighty years. But just try doing without those energizing specks and see how long it is before you start to fall to pieces.

The same considerations exactly apply with the vitamins’ fellow particles the minerals. The fundamental difference between vitamins and minerals is that vitamins come from the world of living things—from plants and bacteria and so on—and minerals do not. In a dietary context, minerals is simply another name for the chemical elements—calcium, iron, iodine, potassium, and the like—that sustain us. Ninety-two elements occur naturally on Earth, though some in only very tiny amounts. Francium, for instance, is so rare that it is thought that the whole planet may contain just twenty francium atoms at any given time. Of the rest, most pass through our bodies at some time or other, sometimes quite regularly, but whether they are important or not is still often unknown. You have a lot of bromine distributed through your tissues. It behaves as if it is there for a purpose, but nobody yet has worked out what that purpose might be. Remove zinc from your diet and you will get a condition known as hypogeusia, in which your taste buds stop working, making food boring or even revolting, but until as recently as 1977 zinc was thought to have no role in diet at all.

Several elements, like mercury, thallium, and lead, seem to do nothing good for us and are positively detrimental if consumed excessively.* Others are also unnecessary but far more benign, of which the most notable is gold. That is why gold can be used as a filling for teeth: it doesn’t do you any harm. Of the rest, some twenty-two elements are known or thought to be of central importance to life, according to Essentials of Medical Geology. We are certain about sixteen of them; the other six we merely think are vital. Nutrition is a remarkably inexact science. Consider magnesium, which is necessary for the successful management of proteins within the cells. Magnesium abounds in beans, cereals, and leafy vegetables, but modern food processing reduces the magnesium content by up to 90 percent—effectively annihilates it. So most of us are not taking in anything like the recommended daily amount—not that anyone really knows what that amount should be. Nor can anybody specify the consequences of magnesium deficiency. We could be taking years off our lives, or points off our IQ, or the edge off our memory, or almost any other bad thing you care to suggest. We ju...

In a normal diet it is almost impossible not to overload on sodium, because there is so much salt in the processed foods we eat with such ravenous devotion. Often it is heaped into foods that don’t seem salty at all—breakfast cereals, prepared soups, and ice cream, for instance. Who would guess that an ounce of cornflakes contains more salt than an ounce of salted peanuts? Or that the contents of one can of soup—almost any can at all—will considerably exceed the total daily recommended salt allowance for an adult?

Archaeological evidence shows that once people settled down in agricultural communities they began to suffer salt deficiencies—something that they had not experienced before—and so had to make a special effort to find salt and get it into their diet. One of the mysteries of history is how they knew they needed to do so, because the absence of salt in the diet awakes no craving. It makes you feel bad and eventually it kills you—without the chloride in salt, cells simply shut down like an engine without fuel—but at no point would a human being think: “Gosh, I could sure do with some salt.” So how they knew to go searching for it is an interesting question, particularly as in some places getting it required some ingenuity. Ancient Britons, for instance, heated sticks on a beach, then doused them in the sea and scraped the salt off. Aztecs, by contrast, acquired salt by evaporating their own urine. These are not intuitive acts, to put it mildly. Yet getting salt into the diet is one of the most profound urges in nature, and it is a universal one. Every society in the world in which salt is freely available consumes, on average, forty times the amount needed to sustain life. We just can’t get enough of the stuff.

A very big part of the history of the modern world is the history of spices, and the story starts with an unprepossessing vine that once grew only on the Malabar coast of southwestern India. The vine is called Piper nigrum. If presented with it in its natural state, you would almost certainly struggle to guess its importance, but it is the source of all three “true” peppers—black, white, and green. The little round, hard peppercorns that we pour into our household pepper mills are actually the vine’s tiny fruit, dried to pack a gritty kick.* The difference between the varieties is simply a function of when they are picked and how they are processed.

Incidentally, the long-held idea that spices were used to mask rotting food doesn’t stand up to much scrutiny. The only people who could afford most spices were the ones least likely to have bad meat, and anyway spices were too valuable to be used as a mask. So when people had spices they used them carefully and sparingly, and not as a sort of flavorsome cover-up.