From 1793 to 1822 yellow fever was one of the most dreaded diseases in the port cities of the United States. Statistically, one can dismiss it as inconsequential in comparison to tuberculosis and smallpox. Yellow fever did not kill that many people, but during that period, it struck with such ferocity in principal cities that it spread gloom and fear throughout the country. Doctors were uncertain of the cause of yellow fever and the factors that led it to reach epidemic proportions.

That uncertainty was not unique. The causes of other diseases were also unknown. But doctors and patients then had an acute understanding of fever. Today, fever is a symptom that can usually be controlled with over-the-counter medicines. Then, fever was tantamount to disease itself.

 Engraving of Benjamin Rush, M.D., by Richard W. Dodson, after a portrait by Thomas Sully.
Engraving of Benjamin Rush, M.D., by Richard W. Dodson, after a portrait by Thomas Sully.

Fever was far more than a question of body temperature and discomfort. It was a state in which a person’s whole being was reordered. Two hundred years ago it was conceived in much the same way that we conceive of cancers. Just as today, when one discusses cancer, death is assumed to be a likely consequence, then when one discussed fever, death was assumed to be a likely consequence. It was this view of morbidity that made yellow fever so feared simply because in the experience of these people who were so sensitive to fevers, yellow fever was most powerful and horrible.

Yellow fever was also exotic. Epidemics prior to 1793 all seemed to be exceptions. Philadelphia, for example, had epidemics in 1699, 1741 and 1762. Yet when Dr. Benjamin Rush faced the onslaught of yellow fever in 1793, he could find nothing written on those early epidemics.

He inspired his old mentor, Dr. John Redman, to write about his experiences in 1762. Rush did have a published monograph on the 1745 epidemic in Charleston, South Carolina, and unpublished letters on a 1741 epidemic in Virginia. So prior to 1793 the country’s experience with epidemic fevers was dominated by malaria, then called the intermittent (if mild) or remittent fever (if severe), the many childhood illnesses, scarlet fever perhaps being the most frightening, and smallpox. However, since mid-century, smallpox was thought to be manageable by a regimen of inoculation. That said, extraordinary congregations of people, such as occurred in the massing of troops during the Revolution, did lead to deadly smallpox epidemics.

Yellow fever was considered a disease of the tropics, and it entered the lives of American families primarily as a scourge claiming the lives of sons and brothers who voyaged to the West Indies, at that time America’s principal partners in trade. In the tropical context, where deadly varieties of malaria were far more common, yellow fever was not of special concern.

One exposure to yellow fever conferred lifetime immunity (a fact not understood at the time) so among the natives and creoles on the islands there was a large pool of immune people. In addition, slaves brought from West Africa likely had exposure to the fever there. In general, children survived the disease better than adults. So in areas where yellow fever could be said to be endemic, many people could not get the disease.

We know today that yellow fever is a virus spread by the Aedes aegypti mosquito. This mosquito has peculiar habits which we are continuing to learn about. Its most distinguishing feature from other mosquitoes is its preference for urban habitat. It breeds best in relatively clean standing water and outdoor cisterns were a prominent feature among many city houses in that day before indoor plumbing. It also feeds during the day, and so must have quite enjoyed the bustling scenes common at the quays of the major port cities of the 18th century. Finally, it has no trouble adapting to life inside a house or a ship. Thus in a day when window screens were unknown, it had ready access to relatively unprotected environments.

In the 18th century the epidemiology of yellow fever was a matter of great dispute. But in retrospect we can see how the disease found a foothold in cities like Philadelphia, and why the disease spread with such devastation. The trade with the West Indies provided ships that were essentially small cities, with their cisterns of water, crowded conditions and concealed spaces, plying the seas frequently between the natural tropical habitat of the mosquito and temporary refuges in temperate climes where the pool of immune people was constricted to seamen with experience in the West Indies, those born in Africa, and survivors of the two earlier epidemics in 1741 and 1762.

Still of some mystery is why, given those condition, yellow fever wasn’t a more frequent visitor to American ports. In the current discussion of global warming, many are warning that warmer temperatures will bring tropical diseases like yellow fever and malaria to the north. However, malaria was epidemic in many northern areas, and even endemic in ideal habitat during the 17th century in a period known as the Little Ice Age. Most likely, like many lifeforms, either the Aedes aegypti mosquito or the yellow fever virus or both, have periods of greater virulence dependent on factors still not understood.

In any case, in early August residents of Philadelphia’s Water and Front Streets near the quays began dying of a fever in a matter of days exhibiting uncommon symptoms. By the end of August those symptoms which distinguished yellow fever from other fevers had become notorious.

Perhaps the most insidious was the conviction of the victim that he was getting well. The fever had a remission two to three days after the on-set of symptoms of nausea and general debility which sent some victims back to their jobs and into the streets only to drop dead.

As the disease matured so did the horror of the symptoms. There could be bleeding at any and every orifice of the body, even through the pores of the skin. Vomit came out black. There could be constant hiccuping so that relatively lucid moments provided no comfort. Not a few fevers course their way through the body seemingly capricious in the pain they inflict. Yellow fever did so with uncommon destructiveness of bodily functions with the embarrassing side effect that the victim could still almost to the end suffer the delusion that he or she was getting better.


This demeaning of the yellow fever victim was doubly demoralizing because unlike in most infectious diseases the principal victims were not the elderly and children. The first group recognized as prone to get it were males between the ages of 15 and 40. Thus many heads of family were victimized.

Soon enough, the community realized that the disease was not confined to any one age group or sex. Even an early hope that blacks were exempt was soon dashed. Finally, while most diseases spread in areas of filth among people who are impoverished, the yellow fever mosquito could thrive among the hallmarks of cleanliness — the full water cistern in back and the spacious houses of the rich.

Profiling of the victims of yellow fever highlights the power of the disease. Today, social historians commonly use it as a marker of the extent of poverty in cities like Philadelphia, showing that the poor in crowded alleys were its principal victims. At the time, not a few grabbed onto the same statistics with the same, for the rich, hopeful conclusions, but the general gloom about the disease spread because it was clear throughout that no one was exempt. Even Samuel Powell, a former mayor, one of the city’s richest men, with access to country homes and personal round the clock attendance of physicians, fell a victim to the fever.

Benjamin Rush was the first to recognize the disease as yellow fever.

A man of great energy, he took an activist approach to the disease. While this seems a common enough trait in a medical man today, recall that in the 18th century what passed for medical practice was frequently ridiculed. During epidemics, doctors were as prone as preachers to point out that all was in the hands of God.

From the beginning Rush’s activism was challenged. Until the middle of September when upwards of 50 people were dying a day, some doctors continued to deny that there was truly an epidemic of yellow fever. Like all activists Rush was a public man and he was eager to enlist institutions, some that he helped create, in the fight against the disease.

In late August the College of Physicians issued instructions, written by a committee dominated by Rush, on how to avoid infection — essentially by moderating all habits, and disinfecting homes with vinegar and camphor, avoiding victims and creating a fever hospital to care for victims. To provide nursing to those abandoned victims, Rush also inspired the city’s African Society to provide nurses under the theory that blacks could not get the fever.

Needless to say the response of many to this was flight from the city. However, most historians over estimate this response. In large part this is because a goodly portion of the primary documents about the fever were written by those who fled (even the principal “instant history” written by Mathew Carey.) Understandably those who fled wanted to paint a bleak picture of the situation they faced in the city and associate their own flight with a widespread and seemingly rational reaction to the situation.

Compared to later epidemics, the hallmark of the 1793 epidemic, was how many people stayed barricaded in their houses. Business did not continue as usual. Not only was the port quarantined by most of the world, but Philadelphia itself banned incoming ships for fear that they would bring more disease to the city. However, the Wednesday and Saturday markets continued. Banks remained open, and while mail delivery stopped, the post office remained open. Save for the final two weeks of the epidemic, some churches continued to hold Sunday services.

Thus the varieties of testimony for these virtual captives is startling. There are the almost daily letters of the lonely merchant Thomas Welsh, the almost daily letters of the Quaker merchant and family man Benjamin Smith, Rush’s almost daily letters to his wife, the diary of the Lutheran minister, and the newspapers, one of which published daily except Sunday throughout the epidemic.

It is often written that all the functions of government ceased, highlighted by the flight of President Washington. Actually Washington left on a scheduled vacation at the scheduled time September 10, some days after neighbors and even a cabinet member, Alexander Hamilton, had taken the disease. And he had a job to do: officiate at the laying of the cornerstone of the Capitol building in the City of Washington.

Of course, the federal government was relatively small then and its functions, save for mail delivery, had little to do with daily city life. Those government clerks in the Treasury who did carry on necessary work for the nation’s commercial life did work in their offices during the epidemic (and letters from some of them remain.) Their bosses did leave but obviously policy decisions were not going to be made during the epidemic.

The state government began the epidemic in full force, with the legislature in session. However, they promptly adjourned after giving the governor more power to enforce quarantines on incoming ships. The governor soon left the city, but not before doing all he could to enforce a clean-up of the city. In his earliest pronouncements Rush blamed rotting coffee on one of the wharves as the spark that set off the epidemic.

That left Mayor Matthew Clarkson and he did not abandon the city. He correctly perceived that the challenge was to find those who needed help and provide food for those who remained. Usually the volunteer Overseers of the Poor guided the city in these functions, sending the poor who were sick to the public dispensary and alerting other charities to their other needs.

The ranks of the overseers were depleted by flights from the city, so Clarkson organized a public meeting to raise volunteers. In a matter of days, a system was set up in which the dead and dying were identified by volunteers going door to door if needs be.

The sick were taken to the fever hospital set up in a temporarily abandoned estate called Bush Hill (last rented by Vice President John Adams then far away in Massachusetts.) A French merchant named Stephen Girard, who would in time become one of the richest men in America, administered the hospital with personal attention that inspired the city.

At first young American doctors treated the sick at the hospital, but soon a French doctor, Jean Deveze, a recent refugees from the black revolt in what would become Haiti, took over. Working in Haiti, he was no stranger to treating yellow fever.

The African Society provided men to cart the victims either to the graveyards or Bush Hill. Clarkson also saw to it that several bakers received enough flour to bake bread for any and all.

By the third week in September a new reality took hold in the city that lasted until the third week of October. It featured quiet streets punctuated by the rumble of the cartmen, save for when the markets were briefly open or the mail was distributed at the post office. Others delivering messages between suffering families also ventured out, as did boys delivering newspapers, and those not few citizens who thought themselves out of danger.

The other great exception was the Quaker’s Yearly Meeting. They decided not to doubt the wisdom of God by postponing the meeting due to an epidemic that was itself a visitation from God. So delegates from around the nation and city came to the meeting house in the heart of the epidemic.

And then there were the doctors. While we look upon the medical practices of the late 18th century as only marginally better than that of the Middle Ages, there was a belief at the time that, as in all things during that Age of Enlightenment, rational inquiry was making medicine better and that rapid advances were in store.  Some like Rush could combine Enlightenment rationalism with religious Millennial conceit and think that advances in medicine in part heralded the second coming of Christ.

Within two weeks of the public recognition of the severity of the epidemic (which was about August 25), four doctors offered public explanations of the disease and its treatment. Among the four were perhaps the two most prominent doctors in the city, Rush and Adam Kuhn.

All the doctors disagreed and soon the controversy between them became disagreeable. In a nutshell, traditional practice at the time dictated that a debilitating disease like yellow fever should be treated with stimulants including wine, “bark” which was a liquid distilled from the bark of a Peruvian tree, and cold baths. Rush advocated a different approach. He thought the debility of the fever in itself a deadly stimulus to the body and that it best be counterintuitively fought with heroic depleting remedies, primarily calomel purges and copious bleeding with the lancet (leeches were not popular in Philadelphia then and would be far too slow for Rush’s purposes.)

Most historians favor the former treatment. While ineffective it did not make the patient any worse off. However, I feel that Rush accurately identified the drama being played out. Yellow fever does kill by the shock it administers to the system so why not weaken the patient and prevent the body from over-reacting to the stimulus of the disease?

Most doctors and many patients were won over to Rush’s basic approach. Recall that many of the victims were in their prime of life, one did not react to a violent mortal disease by sipping tea. Soon some purging and bleeding became commonplace. Even doctors who historians hail as gentle practitioners, like Deveze, did bleed, and resorted to blisters on the neck and head (which required shaving the head) and hot bricks placed on the extremities to try to revive dying patients.

Rush also accurately identified the varieties and stages of yellow fever. In some victims the virus has little effect; others have disturbing symptoms that last only a few days; and others either get the fever in full force immediately and die almost as if poisoned or have a horrible relapse on the third or fourth day of the fever and are often dead a few days later.

From society’s experience with smallpox, it was common in that day to prepare the body for disease. In the process of inoculation, patients were isolated, purged and put on a special diet, and then exposed to smallpox in hopes that they would, under constant care, have the disease lightly and then remain immune to it for the rest of their lives. Using the same thinking, Rush urged people to take purges and be bled at the slightest onset of illness.

It was this, usually, self medication of strong purges that alarmed other doctors. Estimates of the number of dead during this epidemic range from 3,000 to 5,000. The official total was 3,881. Very few were observed by doctors and there were no scientific accounts of their manner of dying. There were a few autopsies which illuminated the obvious, the stomach was quite overwhelmed.

However, two observations grabbed hold of the city’s imagination. The first was that the appearance of black vomit invariably meant the patient would die. The second was that patients who evidenced ptyalism or the constant drooling of saliva in the mouth after taking mercury compounds all recovered. This ptyalism was caused by what we now call mercury poisoning.

Mineral mercury (we can now identify organic mercury compounds) is the primary ingredient of calomel, a medicine first developed in the 16th century. In 1793 it was not considered a poison and when oral doses didn’t bring on salivation, doctors rubbed mercury ointments on the patient’s gums. The name “calomel” refers to its sweet, honey-like taste, that made it much easier to swallow than the usual fever remedy, bark, which was rather bitter.

Thus the typical yellow fever patient was confronted with a frightening fever of uncharacteristic violence and, by many of city’s doctors and newspapers, encouraged to take violent remedies that cause vomiting and severe diarrhea combined with continuous bleeding which could lead to an at least groggy if not comatose state.

But bear in mind that it was often not the patient who decided what remedies would be tried but those family members watching them. The depleting remedies favored by Rush at least had the advantage for family members of making the yellow fever victim manageable, not liable to run out in the streets in the throes of delirium.

That said, Rush also broadcast his remedies as preventatives urging that people feeling any premonitions of fever take calomel and get bled. In the modern context when preventatives rarely debilitate and are designed to strengthen the body, Rush’s campaign seems in retrospect to have been absurd. But Philadelphia was confronted with an epidemic killing a little over a hundred people day despite several thousand people leaving the city. To many strong measures seemed in order.

Rush jumped to the conclusion that not only those who took his remedies and did not die were cured by his remedies but also those who took his remedies as preventatives and who did not get the disease were cured by his remedies. Thus he claimed that of 100 people who took his remedies only one died.

Compared to medicine today, medicine then did not show the circumspection that is the hallmark of a generally successful profession. Medicine then had few success stories. Inoculation for the prevention of smallpox was perhaps the foremost and to effect that patients had to undergo a considerable ordeal as they were infected with a minimized exposure to matter from smallpox pustules while being treated with medicines, often calomel, while under a doctor’s supervision and usual in a group of patients. The hope was that they would have a mild case of smallpox that would assure lifetime immunity from the disease.  

Meanwhile, Dr. Deveze did manage patients at the Bush Hill hospital which took an approach that seems more reasonable to us. In anticipation of the possible violent symptoms the fever might exhibit, a patient did not have to be treated with violent remedies. Deveze treated symptoms as they arose. However,  there is no evidence that this increased the chances of survival. Deveze criticized Rush’s purges for so deranging many patients’ stomachs that nothing could be done to save them.

In speculating on this competition between doctors, it should be remembered that, because of the crisis, getting to either Rush or Deveze or their many disciples was problematic. Sickness kept Rush in bed for a couple weeks and Deveze was out of town. A family had to summon the courage to send a loved one by cart to the hospital in a context which was unfamiliar to them. In the experience of the city, hospitals provided care for those with long term conditions, especially insanity. The yellow fever hospital was being invented as the epidemic progressed and it closed when the fever ended.

Most of the victims of the fever in Philadelphia suffered beyond the help of the doctors.

Successive frosts in mid-October began decreasing the incidence of new fever cases. By early November the epidemic was over. People returned to the city and business resumed, ships finally coming up river and merchants displayed their fall goods. After some initial doubts, the federal government returned and Congress resumed its session on schedule in December after a recess of several months. The volunteers who held the city together were hailed as heroes, save for the blacks who were unjustly accused of profiting from the epidemic either through pilfering abandoned houses or charging exorbitant sums for nursing victims.

The sacrifice of the doctors, several died, was also noted, as well as the work of the preachers who remained. However, the sacrifice of the doctors and preachers soon became problematical because for both groups the epidemic’s end was the beginning of a new campaign. The preachers led a campaign of moral reform highlighted by a failed effort to get the state legislature to ban theatrical entertainments. The doctors engaged in a heated controversy about the origin of the disease. Rush argued that the seeds of yellow fever were engendered by the filth of the city.

His opponents, and there were many, argued that the seeds of the disease came from the West Indies. The governor embraced both ideas calling for greater civic cleanliness and stricter quarantines and inspection of incoming vessels.

From our vantage point, these debates were moot, all suffering from any inkling of how the disease was spread. If yellow fever retreated for another 30 or 40 years, as it seemed to be in the pattern of doing, the debates would have soon ended. However, yellow fever returned.

During the 1793 epidemic it became clear to many that an epidemic in New York City in 1791 was yellow fever. The city establishment had suppressed almost all discussion about the epidemic. In 1793 New York as well as most other cities in the nation instituted strong quarantines against people fleeing from Philadelphia, turning them away a gunpoint in some places. Baltimore had one of the strictest quarantines. And not without gratification to some in Philadelphia, in 1794 Baltimore was struck with an epidemic.

City officials tried to keep news of the epidemic out of the newspaper or “spin” it as just a common fever, but other cities quarantined Baltimore, and a young student of Rush’s sent out letters describing all the characteristic symptoms of yellow fever. His memoir of the epidemic provides one of the best collection of case studies of yellow fever victims at that period. At the same time, New Haven, Connecticut, had an epidemic. Around 200 people died in Baltimore and 64 in New Haven but the nation was served notice that the great epidemic of 1793 might not be a quirk.

Indeed Rush discovered a few cases of suspected yellow fever in Philadelphia and used them to write another memoir about yellow fever, outlining more ideas about preventatives and cures. For the latter he placed even more emphasis on frequent and copious bleeding, and to prevent the fever listed many vegetables whose putrefaction could engendered disease. He arrived at this not by experimentation but by a search of the medical literature dating back to the Ancient Romans. He also encouraged a system of quarantine and enforced clean-ups on a block by block basis when yellow fever struck.

In a sense the public health history of the 1790s became a case of public authorities finally grasping the lurid reality that Rush and others began painting for them. From our perspective the epidemics seem rather limited episodes both in time and space. But epidemic is a tricky word. We use it now in a time and place where we are largely exempt from common everyday infectious diseases more serious than the common cold. In the 18th century calling a disease epidemic was only a way of distinguishing something relatively uncommon from the daily incidence of often deadly infectious diseases.

Noah Webster noted an influenza epidemic in 1793 and in part through his efforts, the country’s first medical and scientific magazine, The Medical Repository, began publishing and its major focus was on fever epidemics around the country. In an earlier publication Webster collected essays on fevers in New York, New Haven and rural Massachusetts. Webster began embracing the Classical notion that epidemics were caused by “the epidemic constitution of the atmosphere,” which Webster soon postulated could maintain the current state of national ill health for another fifty years.

The nation did not have long to wait before the lurid reality of a major yellow fever epidemic returned. But setting the scene for that were two mild epidemics, the first in New York City in 1795 that killed about 730 and the second in Philadelphia in 1797 that killed 1100. Those death tolls are startling enough, but the victims were confined to certain sections of the city. New York actually boasted that most of its victims were strangers and people of little account — don’t be fooled by the minister who died, he was just a Methodist!

In Philadelphia a system of block by block quarantines with cleanups was tried with mixed success. Many residents and even doctors balked at reporting cases of the disease for fear of patients being taken away and denied access to their homes. Yet, the 1797 epidemic seemed to many to have been well managed and many felt that the city could deal with an epidemic without the citizens abandoning the city.

By all accounts the late summer and fall of 1798 was an almost incredible time in American history. Perhaps because of that historians have largely forgotten it, even the historians of the cities that were ravaged by the epidemic. Philadelphia, New York, Boston and many smaller ports in between, had yellow fever epidemics.  At the time the total death toll was estimated by some observers at 10,000. The official numbers are just a little over half that, with some 3,500 in Philadelphia, 1,500 in New York.

Because of their experience with their last epidemic, city officials in both Philadelphia and New York first reacted to the epidemic with some degree of confidence. However, the fever spread so rapidly in Philadelphia that by early September officials gave up any hope of containing the epidemic. They channeled their efforts into setting up camps in the countryside and inviting those without other places of refuge to go there.

New York officials stubbornly adhered to the notion that the fever was centered in only certain areas of the city, and even in those areas, rather than evacuate people, the city established soup kitchens to lessen the disruption caused by the growing number of deaths. In retrospect the health committee decided that was a mistake. The only bright side to these epidemics was that early frosts brought them to an early end.

As it turned these were the last major yellow fever epidemics in these northeastern ports. However, the fear of epidemics remained. More families left the city during the late summer as a matter of practice and at the first sign of an epidemic, evacuation was widespread. A larger portion of people left Philadelphia during the small epidemics of 1799 and 1802 than did in 1793. New York’s last epidemic of note in this period was in 1805.

Needless to say both these major cities continued to try to prevent the recurrence of the epidemic. Even the federal government became involved. The first order of business President John Adams mentioned in his 1798 annual message was the possible need for stricter quarantines enforced nationwide. Civic leaders in Philadelphia proposed a three pronged attack: cessation of trade with the West Indies during the summer months, a municipal water system to bring “pure” water in the city, and a redoubled effort to clean privies, and disinfect the houses of the poor. New Yorkers also embraced the idea of an improved water system.

Very little work has been done by historians on the social effects of the epidemics. Did they contribute to the religious revival called the Second Great Awakening? Did they contribute to disillusionment with the Federalist Party? Certainly the epidemics defeated the plan of Philadelphia officials to try to persuade the federal government not to move to the new city of Washington. And the state capital soon moved to Lancaster. In 1798 the Quaker’s once again had their Yearly Meeting during the height of the epidemic but the death toll among their society became too great and they rescheduled their Yearly Meeting for April, and have met then ever since.

However the effects of the epidemics on medicine are clearer. The fear of any fever became such (and doctors like Rush suggested that any fever given the right local conditions could develop into yellow fever, that heroic depleting remedies, especially bleeding, became increasingly popular. That in turn fostered alternative medicine highlighting herbal remedies and in the case of homeopathy minimal doses of medicine.

An unfortunate result was that at this time when medical concerns came to the forefront as never before, medicine offered the wrong answers and dangerous remedies. In the later epidemics some of the most prominent victims were doctors and newspaper editors. Both groups sacrificed themselves to stay on the front lines of the epidemics, an essential service for the nation only, tragically, to supply misinformation.

Yellow fever returned for a brief encore in northern cities in 1822. After that it confined itself to southern ports and river cities. Portsmouth, Virginia, on one end of this arc and New Orleans on the other had the deadliest single epidemics. In the 1878 a devastating epidemic ravaged the Mississippi Valley as far north as Memphis. However, in general after 1820 the profile of the fevers suffered by the nation began to change. In New England even the prevalence of intermittent fevers (malaria) was soon forgotten. By the 1830s Baltimore had far fewer of what we know now were mosquito borne diseases. (However, the upper Mississippi Valley remained a hotbed of malaria, as well, of course, as the South.)

Not that northern cities necessarily became healthy. Cholera became the feared deadly epidemic. Other diseases like dysentery and typhoid arising from poor hygiene and overcrowding became more commonplace. However, while these diseases could kill any age, they generally culled the old and young.

So in many respects the yellow fever epidemics stand as unique crises, striking the capital and major cities of a rather proud new nation, and striking the strong and powerful as well as the poor. That in part explains why they were not memorialized then and are scarcely studied today. There is always a certain degree of denial mixed into any country’s history. Certainly today we tend to analyze the birth of the Bill of Rights to death, while ignoring the bills of mortality in the 1790s. And then those social historians who do study those bills of mortality find in yellow fever a chimerical subject for study, and prefer the endemic killers which produce valid statistics.

Yet it bears remembering in the colorful and delicious days of early fall when the landscape is relieved of any hint of the tropics, that in the 1790s many cowered in their houses fearful of black vomit and blood coming out of their ears, while a tiny mosquito, quite out of its element, romped in a brief orgy of blood and death.

By  Bob Arnebeck