1

A DISEASE OF MARINERS

Want to learn to pray? Then go to sea.

—sixteenth-century Spanish proverb1

THE LONGEST VOYAGE AND A NEW DISEASE

On a hot July day in 1497, four ships carrying about 170 men under the command of Vasco da Gama set sail from Lisbon bound for India.2 King Dom Manuel was not willing to leave his cool mountain retreat to see the fleet off, but nobles wished da Gama and his men Godspeed from the dock. The citizens of Lisbon lined the banks of the Tagus River to cheer the ships on their way. They hoped the expedition would make Portugal a commercial power by breaking the monopoly that Genoa and Venice held as the European ends of the Silk Road.

Da Gama’s expedition culminated efforts that had begun during the reign of Henry the Navigator (1394–1460). With the support of the Crown, Portuguese ships inched their way down the west coast of Africa. In 1488, Bartolomeu Dias and his crew became the first Europeans to round the Cape of Good Hope, but his crew, afraid to venture farther into unknown waters, forced him to return home without exploring beyond the tip of the continent. Nevertheless, by locating the bottom of Africa, he instilled confidence that the Indian Ocean was not enclosed by land, as fanciful Greek maps had depicted. He confirmed that a sea route from the Atlantic to Asia existed.

In 1483, King João II and his advisers met with Columbus, who proposed a path to the East Indies by sailing west. The Portuguese were unimpressed with Columbus and knew that he underestimated the circumference of the Earth. Having knowledge of the coast of Africa, they placed their bets on sailing east. So King João II and his successor, King Dom Manuel, charged Vasco da Gama with forging a route around the southern tip of Africa to India.

We know little of the early life of Vasco da Gama nor why the kings chose him rather than Dias to lead the expedition. Da Gama was only in his thirties, but he had seafaring experience and was a member of minor nobility with unquestioned loyalty to the Crown. Arrogant and quick to anger, he was a forceful leader with the ambition and courage to venture into the unknown.

An anonymous member of da Gama’s crew wrote an account of the expedition.3 “They left on their errand with the blessings of the Church, in the favor of their king, and amidst the acclamations of a sympathizing people.” They sailed down the coast of Africa and landed at the Cape Verde Islands. One ship, carrying Dias, returned to Lisbon. The three others, two carracks and a smaller supply ship, set off for Asia. As the journalist states laconically, “On Thursday, August 3, we left in an easterly direction.”

What he did not say was that after the ships crossed the equator, the commanders made an audacious decision. Rather than continue southward, hugging the coast of Africa and remaining within known waters, they veered away from land into the open Atlantic Ocean, probably coming within six hundred miles of the coast of Brazil. They took this circuitous route to capture the prevailing westerly trade winds in hopes of being propelled around the Cape of Good Hope.

Why did they think this would work? As far as we know, Bartolomeu Dias and his men were the only Europeans to have sailed to the far southern Atlantic coast of Africa in their 1488 voyage. Dias had veered somewhat to the west and was able to take advantage of the trade winds to carry him around the cape. Presumably, da Gama sailed almost to South America before encountering westerly winds. It was an act of remarkable daring.

His daring was not rewarded. His ships did not round the tip of Africa on the first attempt but struck land just north of the cape. They had been out of sight of land for ninety-three days, likely the longest uninterrupted ocean voyage ever undertaken at that time. The men were suffering from dysentery, fever, and a shortage of drinking water. They collected water, meat, and fish upon landing; however, no fruits or vegetables were to be found. Fighting unfavorable winds and weather, they eventually rounded the Cape of Good Hope and landed on the east coast of Africa.

They then pushed on beyond the point at which Dias’s crew had been afraid to venture. This demanded incredible courage. The first astronauts were unquestionably brave, but they knew what they were facing. Vasco da Gama and his men knew nothing of the Indian Ocean or of the inhabitants of the east coast of Africa. They had no idea if the locals would greet them warmly as visitors from exotic lands or attack them as hostile invaders. The men’s willingness to venture beyond their known world reflects da Gama’s qualities as a leader, as well as their hopes of sharing in the riches they expected to bring back from Asia.

As they sailed north, a mysterious illness afflicted the crew. Da Gama’s journal provided the first clear description of this illness that was to plague mariners for centuries. “Many of our men fell ill here, their feet and hands swelling, and their gums growing over their teeth, so that they could not eat.” The unknown disease ravaged the crew and men began to die. The explorers had no experience with such an ailment, no name for it, and no idea of what caused it. The ships anchored in the delta of the Zambezi River in Mozambique on January 22, 1498, almost six months after setting sail from Cape Verde.

In Mozambique, there were abundant fruits, especially oranges, growing along the river. The men ate the fruit and quickly recovered. “It pleased God in his mercy that on arriving at this city all our sick recovered their health, for the air of this place is very good.” In keeping with the beliefs of the time, the narrator blamed the disease on the foul air aboard the ship. But the crew immediately recognized the value of oranges and eagerly ate them.

The three vessels proceeded along the African coast. Da Gama’s arrogance in dealing with the local leaders led to several confrontations, some violent, making the voyage more adventurous than it had to be. They eventually reached India, where trading with the local merchants was again marked by conflicts and misunderstandings but no violence.

On the return voyage, they ignored warnings about monsoon winds and struck out on a direct route across the Indian Ocean. And once again the unknown illness reappeared.

Owing to frequent calms and foul winds it took us three months less three days to cross this gulf, and all our people again suffered from their gums, which grew over their teeth, so that they could not eat. Their legs also swelled, and other parts of the body, and these swellings spread until the sufferer died, without exhibiting symptoms of any other disease. Thirty of our men died in this manner—an equal number having died previously—and those able to navigate each ship were only seven or eight, and even these were not as well as they ought to have been. I assure you that if this state of affairs had continued for another fortnight, there would have been no men at all to navigate the ships. We had come to such a pass that all bonds of discipline had gone.4

On January 7, 1499, they anchored at Malindi, now part of Kenya, and the locals sent emissaries aboard. “The captain-major sent a man on shore with these messengers with instructions to bring off a supply of oranges, which were much desired by our sick. These he brought on the following day, as also other kinds of fruit.” The men eagerly ate the oranges. Some were too ill to benefit from the fruit and died; the others recovered rapidly.

Too few men had survived to sail all three ships, so they burned the supply ship and set sail for home in the two carracks. When they rounded the cape on March 20, the remaining crew was in good health.

Da Gama arrived in Lisbon at the end of August 1499. He had lost two-thirds of his crew, mainly to scurvy. His brother, Paulo, who commanded one of the carracks, died on the return voyage. Da Gama had antagonized many of the rulers of Africa and India with his high-handed ways, but in Portugal he was a hero. Exultant men and women of Lisbon again lined the streets to cheer as princes and clergy escorted da Gama to the palace and an audience with King Manuel. The monarch heaped honors and riches upon da Gama but could not grant da Gama’s wish to be given his hometown of Sines as his personal property; it was already the property of a powerful duke. Despite this disappointment, da Gama spent the rest of his life living like a king. And Portugal exploited its newfound access to Asia to dominate that trade. By the end of the sixteenth century, tiny Portugal was second in wealth only to Spain among the European nations. Although Columbus had been wrong about the circumference of the earth, the treasure that Spain looted from the New World was even more valuable than the Asian trade in silks and spices.

AN ERA OF TRADE AND COLONIZATION

Da Gama’s voyage, along with that of Christopher Columbus five years earlier, opened the oceans to European nations and ushered in the Age of Sail. For the next 350 years, thousands of ships crossed the seas at the mercy of the winds. The vessels connected Europe to the rest of the world and enabled the construction of global empires.

The voyage of Vasco da Gama provided the first record of ships sailing on the open ocean continuously for more than a few weeks. Columbus on his first voyage to the West Indies required only thirty-seven days to cross the Atlantic. Before Columbus, sailors had remained close to land and touched shore frequently. European ships had been too small to carry enough men and provisions for months at sea and were not sufficiently seaworthy to survive ocean storms. China had built huge ships, more than five times larger than the biggest European vessels, but they made relatively short hops from port to port around the Indian Ocean. Those ships were designed to flaunt wealth and power, not to sail the open seas. Since the Chinese believed that they were at the center of the universe, they had little interest in exploring beyond familiar waters.

Another limitation to ocean travel was the primitive means of navigation, essentially limited to looking up at the sun during the day and the stars at night when the clouds permitted. Maps were mere sketches at best and pure fantasy at worst. To maintain their bearings, mariners required landmarks. They had to come within sight of land to orient themselves to known geography.

As a result, Europe had been a virtual island. The ocean was to the west, ice closed off the north, and Muslim realms and hostile warrior tribes blocked the south and east. The Crusades had penetrated North Africa, but the Sahara posed a barrier to travel farther south. Since Marco Polo in the thirteenth century, few Europeans had ventured into the Asian plains. Ambitious monarchs yearned to break through these barriers.

The impetus was greed. A thriving commerce brought Asian silks and spices to Europe over the Silk Road, a trade monopolized by Venice and Genoa. Other European nations wanted to muscle in on this lucrative business. They coveted direct access to Asian markets and luxury products without having to pass the goods through a series of middlemen, each marking up prices and extracting a share of the profits. That direct access required long ocean voyages.

Technological advancements fueled these ambitions. Beginning with the Vikings, ship construction had steadily advanced. Progress accelerated with the development of internal frames, which permitted the construction of large ships. The Portuguese had developed the caravel, a seaworthy craft slightly less than sixty feet long and, with fore-and-aft triangular sails, able to sail close to the wind. The Portuguese used the caravel to explore the west coast of Africa. Da Gama’s two primary ships were carracks, larger and sturdier than the caravels, but fitted with traditional square-rigged sails, sacrificing maneuverability for size and seaworthiness. Because of this, da Gama had to sail almost to South America before he could capture the trade winds and turn east.

While ships became larger and more seaworthy, the development of a reliable ship’s compass revolutionized navigation. The Portuguese also benefited from Spain’s expulsion of Jews in 1492. The Jewish astronomer Abraham Zacuto fled to Portugal and brought with him detailed maps of the stars. With the newly invented mariners’ astrolabe, a device to measure the angle of the sun and stars above the horizon on the rolling deck of a ship, the charts enabled sailors to calculate their latitude. These innovations emboldened Europeans to set out on the open sea. The two Iberian nations were the first to venture beyond the virtual European island, and Portugal was the more adventurous.

A DISEASE OF SAILORS

Although Vasco da Gama demonstrated that long sailing voyages over the high seas were feasible and gave Europe access to the world, the length of the voyage required the crew to live on ship’s rations for months at a time. We do not know exactly what da Gama’s men ate while at sea. Without refrigeration, their menu certainly lacked fresh fruits and vegetables.

The journal of da Gama’s voyage provides the first detailed description among seamen of an illness characterized by lassitude, swollen gums, foul breath, swollen and painful extremities, and eventual death. Although the journal blamed the disease on bad air, the men recognized that oranges were a cure and ate them at every opportunity. Having no concept of vitamins, they did not realize that the fruit replaced a vital nutrient, vitamin C, of which they had been deprived for months.

This malady soon became known as scurvy, a word derived from the Icelandic word skybjugr, meaning cut or ulcerated swellings.* An alternative English spelling was scorby, and people suffering from scurvy are scorbutic. In Portuguese and Spanish, the disease is escorbuto. Since vitamin C is the antiscorbutic vitamin, its chemical name became ascorbic acid or ascorbate.†

Although da Gama and his men had never seen the disease before, there had been reports of scurvy before the Age of Sail. Ancient Greek and Egyptian physicians described soldiers and civilians suffering from malnutrition during sieges. They had symptoms of scurvy mixed with features of other diseases. In northern Europe during the Middle Ages, scurvy afflicted the population each winter when fresh vegetables were unavailable and before the potato, which is rich in vitamin C, arrived from the New World. The Crusaders suffered from scurvy and other forms of malnutrition when they invaded North Africa without adequate supply lines.

However, scurvy was not recognized as a specific disease and a prominent concern of medical writers until it appeared among mariners.5 It was perhaps the first disease of technology, a product of innovation in ship construction and navigation, which allowed ships to remain at sea for months at a time.

After about three months of a diet lacking vitamin C, the first signs of scurvy appear. The initial manifestation is lassitude, which becomes profound as the disease progresses. Next, tiny bumps appear around hair follicles, and the hairs develop an abnormal corkscrew shape. The disease is painful; the joints, muscles, and back ache. Tiny hemorrhages, known as petechiae, appear in the skin when capillaries rupture.

As the disease progresses, connective tissues break down. New wounds fail to heal and old ones may open up. Hemorrhages cause swelling of the arms and legs. Blood can leak into the spaces between the bones and the tough connective tissue lining the bones, the periosteum; this type of hemorrhage is virtually unique to scurvy, excruciatingly painful, and a prominent feature of scurvy in infants. Bleeding into muscles and other organs can also occur.

Among people with poor dental hygiene, the gums become soft and swollen, and the teeth loosen in their sockets and eventually fall out. The breath smells horrible. Physicians thought that the gum changes were required to make the diagnosis. It wasn’t until the late nineteenth century that doctors realized that people who have lost their teeth, infants who have not yet teethed, and adults with good dental hygiene manifest few or no gum changes.

The combination of profound lassitude, pains throughout the body, and the inability to eat solid food was agonizing. The disease can be fatal within six months, although the exact mechanism by which death occurs is unknown. In some, hemorrhages occur in the heart muscle or in the lining of the heart. Those with advanced disease may faint if they try to stand and may collapse and die suddenly. At that point, death is a merciful end.

THE PLIGHT OF THE COMMON SAILOR

The technological advances that ushered in the Age of Sail also ushered in the age of colonial empires. European nations exploited the ability to travel long distances not only to trade with distant nations but also to acquire colonies to serve as sources of slaves and raw materials and to provide captive markets for their manufactured goods. England, Spain, Portugal, and the Netherlands were the major colonial powers of this era. They built large merchant fleets and maintained navies to protect them. These fleets demanded the services of hundreds of thousands of sailors.*

The lives of these sailors were unimaginably brutal. The men were imprisoned onboard and not permitted to go ashore while the ship was in port for fear that they would desert. The sailors performed arduous physical labor in four-hour shifts (watches) around the clock. When not on duty, they lived in crowded quarters infested with vermin and insects. The ships had poor ventilation, and everything, including the clothing and bedding, was constantly wet. The stench was terrible. Ships stank from unwashed men crowded together for months at a time in unsanitary conditions, from rotting provisions, and from whatever grew in the bilge water sloshing below deck. In these conditions, infectious diseases, especially dysentery, were prevalent.

To allow the crewmen to perform their labors, they received a high-calorie diet rich in fat and protein. The typical rations of common seamen on an English naval vessel were:

Biscuit half a pound, daily
Salt beef two pounds, twice weekly
Salt pork one pound, twice weekly
Dried fish two ounces, three days weekly
Butter two ounces, twice weekly
Cheese four ounces, three days weekly
Peas eight ounces, four days weekly
Beer one gallon, daily

At times, they also received “portable soup,” a dried cake made from oxen offal mixed with vegetables and preserved with salt.6 When put in hot water, it provided an occasional warm dish. This diet was deficient in vitamin C, as well as vitamin A and the B vitamins thiamin and niacin. As a result, crews often suffered multiple vitamin deficiencies.

Within a century of Vasco da Gama, as long-distance sailing voyages became common, scurvy evolved from an unknown disease to a common affliction of sailors. Sir Richard Hawkins, who led an expedition from England around South America from 1592 to 1593, wrote an especially vivid account of its devastation.7 Hawkins claimed that in his twenty years at sea, he had personally seen ten thousand sailors with the disease. His comment highlights how common scurvy had become and the extent to which commanding officers took it for granted.

Hawkins was from a family with a strong naval tradition. He was the son of an admiral and had extensive seafaring experience, including commanding a ship that fought the Spanish Armada in 1588. The cover story for the public was that his expedition to South America was to discover and map new territories, but the true intent was piracy. He set out to disrupt the commerce of Spain by capturing its merchant ships and plundering its settlements along the west coast of South America.

Three ships and about two thousand men set sail June 12, 1593. Facing unfavorable winds, they did not land in Brazil until October, by which time scurvy afflicted the crew and only twenty-four men on the flagship were healthy enough to man the sails. Hawkins described the primary features of the disease, “a loathsome slothfulness . . . swelling of all parts of the body, especially of the legs and gums, and many times the teeth fall out of the jawes without paine.” He attributed the disease to multiple causes, including bad air aboard ships, spoilage of the ship’s rations, and a weak stomach with poor digestion brought on by a hot climate.

Hawkins believed that scurvy could be prevented by keeping the ship clean; wholesome exercise; eating as little salted meat as possible when in a hot climate; not curing meats or washing garments in salt water; and wearing clean, dry clothing, especially when sleeping. He failed to mention how to accomplish this on ships crammed with two thousand men. He also stressed the importance of diet and advised that every morning each man on board should be given a bit of bread and a drink of either beer or wine mixed with water. But “That which I have seen most fruitfull for this sickness is sower [sour] oranges and lemmons.” He claimed he had less scurvy on his ship than on the other two during the expedition because he gave the men lemon juice until the supply ran out.

Following the beliefs of the times, he attributed scurvy to bad air. “But the principall of all, is the ayre of land; for the sea is natural for fishes, and the land for men. And the oftener a man can have his people to land, not hindering his voyage, the better it is, and the profitablest course that he can take to refresh them.” He followed this practice on his voyage and touched shore often. Although he thought the good air to be the main benefit of periodic landings, he also took every opportunity to collect fresh fruits.

He purchased between two and three hundred oranges and lemons in Santos, Brazil.

Comming aboord of our shippes, there was great joy amongst my company; and many, with the sight of the oranges and lemmons, seemed to recover heart. This is a wonderfull secret of the power and wisdome of God, that he hath hidden so great and unknown vertue in this fruit, to be a certaine remedie for this infirmitie; I presently caused them all to be reparted [shared] amongst our sicke men, which were so many, that there came not above three or foure to a share.8

This echoed the experience of Vasco da Gama, whose crew eagerly ate oranges whenever they were available. Like da Gama, Hawkins recognized that oranges and lemons were curative. That the fruit provided an essential nutrient did not occur to him, and bad air remained the culprit.

Despite his efforts, among Hawkins’s three ships, which had set out with about two thousand men, only seventy-five survived when they reached Valparaiso, Chile, in April 1594. Almost all the losses were from scurvy. Even with his depleted manpower, he captured several Spanish ships and looted two towns. Finally, off the coast of Ecuador, the Spanish captured Hawkins and his few surviving men. Hawkins spent several years in a Spanish prison but eventually found his way back to England. In 1622 he published his account of his adventures.

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At the time, merchants like Hawkins were more assiduous than the Royal Navy in providing citrus juice to their crews. In 1600, the British East India Company sent three ships commanded by Sir James Lancaster to trade with Sumatra. Ten years earlier, Lancaster had led England’s first commercial voyage around the Cape of Good Hope into the Indian Ocean. It was a disaster. He started with four ships and returned with only one manned by a crew of five men and a boy.9 Among other horrors, scurvy devastated his crew.

An anonymous author, presumably an officer aboard Lancaster’s ship, wrote an account of Lancaster’s second voyage.10 The first leg of the trip resulted in an unintended experiment. When the three ships landed at the Cape of Good Hope, Lancaster’s ship had less scurvy than the other two.

And the reason why the general’s [Lancaster’s] men stood better in health than the men of other ships was this; he brought to sea with him certaine bottles of the juice of limons, which he gave to each one as long as it would last, three spoonfuls every morning fasting, not suffering them to eat anything after it till noone. This juice worketh much the better if the partie keepe a short dyet, and wholly refraine salt meat; which salt meat and long being at the sea, is the only cause of the breeding of this disease.11

When they landed along the coast of Africa, the officers made every effort to obtain oranges, knowing that they would cure the men of scurvy. Like Hawkins and da Gama before him, they knew how to prevent and cure the disease, but they remained ignorant of the reason.

During the early 1600s, English and Dutch merchant ships carried lemon juice for the sailors. For this purpose, the Dutch East India Company maintained lemon plantations in Mauritius and South Africa. In 1617 John Woodall, the first surgeon general of the English East India Company, published The Surgeon’s Mate, a textbook of nautical medicine. He advised that oranges, lemons, and limes be taken on all prolonged sea voyages. “The use of the juyce of Lemons is a precious medicine and well tried being sound and good.”12 Usually, the juice was saved to treat cases of established scurvy and used as a preventative only if stores were abundant.Even as a preventative, it was not uniformly effective. The juice lost its potency after a few weeks’ time in storage.

Woodall’s advice was ignored. By the middle of the 1600s, partially due to its expense and partially due to its inconsistent benefits after storage, the provision of lemon juice was rare, and scurvy remained the most common cause of death of seamen. In the late seventeenth and early eighteenth century, it mainly affected merchant ships, as naval vessels often remained close to shore, protecting their home countries. Later in the eighteenth century, a shift in tactics led to naval ships remaining at sea for prolonged periods, blockading enemy ports or patrolling hostile shores where they could not land and reprovision. This made scurvy the scourge of both naval and merchant seamen.

The loss of men was astonishing. During the Seven Years’ War from 1756 to 1763, of the 184,899 men who served in the Royal Navy, 133,708 were listed as lost, either to disease or desertion. A detailed breakdown of the diseases was not provided, but scurvy was the most frequent. During the American War of Independence from 1774 to 1783, a total of 170,910 men served in the Royal Navy’s West Indies Fleet, which patrolled the Caribbean and South Atlantic. Of these, 1,243 died in action, whereas 18,545 died of disease. In the tropics, most of these deaths were a result of infections, but four to six thousand were due to scurvy. However, the biggest loss was from desertion: almost a quarter of the sailors—42,069 men—took the opportunity to escape the miserable conditions aboard the ships.13

Scurvy could determine the outcome of sea battles. It is likely that the defeat of the Spanish Armada was at least in part a result of the debilitation of the Spanish sailors by scurvy, having been confined to their ships eating a sailor’s diet longer than the British. Although the Spanish did not specifically document the ravages of scurvy, they did note that when the armada returned to Spain, more than four thousand sailors were on the sick rolls, most suffering various forms of malnutrition.14

Scurvy also occurred on land, especially in prisons, and in both military and civilian populations during prolonged sieges. Although it occurred in northern Europe during the winter, it did not afflict the indigenous people of North America. They knew how to stave off the disease. The Inuit ate raw seal liver, which contains large amounts of vitamin C, and other indigenous peoples drank infusions prepared from evergreen trees, a source of the vitamin, during the long winters.

This knowledge saved one group of European explorers. In 1535, Jacques Cartier led a French expedition up the Saint Lawrence River searching for the Northwest Passage. When forced to overwinter in northern Quebec, scurvy emerged among his men. Out of 110 men, all but three suffered from the disease and twenty-five died. From a chance encounter, Cartier learned from a native that a tea prepared from an evergreen tree, perhaps an arborvitae, would cure the disease. Taking advantage of this wisdom, the remaining members of the expedition survived the winter. Apparently, Cartier did not pass this knowledge on to subsequent French expeditions to Canada, as they continued to suffer from the disease.15

THE CONTINUING MENACE OF SCURVY

It is estimated that prior to 1850 the Royal Navy lost more than one million men to scurvy. Other European nations did not catalog their losses so carefully, but they also suffered tremendous attrition from the disease. In view of the belief of many commanders that citrus fruits could cure scurvy, it seems incredible that authorities did not institute effective preventive measures. There were several reasons for this failure.

First and foremost, no one understood the mechanism by which scurvy afflicted sailors. Before the late nineteenth century, general malnutrition was understood, but there simply was no concept of a disease being caused by a deficiency of one specific nutrient. The idea that a person could suffer a nutritional deficiency while being supplied with plenty of food and without losing weight was alien.

When the early observers saw scurvy being cured by lemons and oranges, they looked for explanations that fit with theories of disease prevalent at the time. Diseases were all thought to result from an external agent acting on the individual. That eating fresh citrus fruits cured scurvy did not prove that the disease was nutritional. We know antibiotics cure infections, but we also know that infections are caused by microorganisms, not by a nutritional deficiency of antibiotics.

The prevailing theory of disease was the humoral theory, which harkened back to second-century Greek writers Hippocrates and Galen. The theory posited that there were four humors: blood, phlegm, black bile, and yellow bile. When an individual was healthy, these four humors were pure and in balance. Disease resulted when something external to the individual contaminated or upset the balance of these humors. The humoral theory was prevalent in European medical teaching until the eighteenth century.

One idea of the time was that bad air, or miasma, could poison the humors. Miasma emanating from damp soil was thought to explain why Europeans suffered so many diseases when traveling to the tropics. Human-to-human contagion was understood in principle, but transmission of microorganisms by insects or other environmental vectors was not understood until the discoveries of Pasteur, Koch, and Lister in the late nineteenth century. Hence, the tropical air was made the culprit. The concept that bad air caused disease was popular from the sixteenth century on and received a boost in the late eighteenth century when the discovery of oxygen and other atmospheric gases piqued interest.

The conditions aboard sailing ships were indeed abysmal, and the air was especially bad. Knowing nothing of microorganisms or vitamins but directly experiencing the stench, writers blamed the foul-smelling air for causing disease. The oranges were assumed to counteract the effects of the air in some unknown manner.

A consistent observation of commentators was that scurvy was a disease of common seamen; officers rarely suffered from the illness. Given the strong class system of the times, the common seamen—all from the lower classes—were blamed for their own misery. Writers invoked traits such as laziness, poor hygiene, and debauchery to common sailors, rendering them susceptible to diseases the upper classes escaped. The officers never thought their more varied diet and freedom to go ashore when in port might be the explanation.

Finally, prior to the invention of refrigeration, there was no way of storing fresh fruits and vegetables on ships during long voyages, and vitamin C in citrus juice lost its efficacy with storage. Merchant ships were at the mercy of the winds, and their captains were reluctant to waste time by detouring to ports to take on fresh supplies. Naval vessels were frequently patrolling hostile shores for months at a time, and it would have been expensive and risky to shuttle provisions to them using supply ships.

Because of these misunderstandings, mariners and those on land continued to suffer and die from a deficiency of vitamin C. Nothing could be done without a new approach to understanding the disease.