There is nothing dirtier than walking down the street, and then suddenly 'flats!'. You make a huge slide over fresh dog poop. Nowadays dog owners have to clean up the poop, because it is dirty and unsanitary. But did you know that in the Middle Ages people also pooped on the street? Just, in front of everyone? We find that dirty now, but in the fourteenth century that was quite normal.
The rain eventually washed the poo into the canal. As the population of the cities increased in the fifteenth century, the stench became almost unbearable. Moreover, the local beer production was dependent on the water from the canals. That would probably not have helped the taste of the beer. That is why the city council of, among others, the municipality of Delft ordered that every house in the city should build a cesspool.
A cesspool was a cellar or pit that was built behind the houses. Cesspools were not only the forerunners of our current toilet, they were also used to dispose of household waste. At the top, the cesspool was provided with a vault, making the whole look like a kind of beehive. The cesspool was dug in so that the vault was just below the ground. A chute was built on the side or at the top through which the poop and household waste could fall or slide.
Archaeologists investigate an excavated cesspool on the Doelenstraat in Alkmaar.
Treasure digging
For archaeologists, cesspools are real treasure troves. Often the most beautiful finds come out, such as jugs, jugs, plates, shoes, spoons, and candlesticks. Even more important is the archaeological value. Cesspools can tell us many things about the former users. In some cases, scientists can deduce from cesspools whether the owners were wealthy, and what their social status was. It also happens regularly that we find indications of what their profession was, or the state of their health… Often even the eating pattern can be traced. Investigating cesspools to find out eating patterns is the work of archaeobotanists. That is a term for scientists who use their knowledge of plants for archaeology.
Archaeobotanists take a sample of the 'bear' (poo) at the dig site and then take a closer look at it under a microscope in a laboratory. But doesn't that smell like a cesspool? “No,” laughs Henk van Haaster, archaeobotanical specialist at the Biax company, “the actual 'bear' has long since perished. We only find things like seeds, bones and small plant remains. It does feel very dirty and slippery. It's just like forest land or horse poop, it can even smell quite nice.”
Results
Once in the lab, the bear sample is sieved and rinsed with water to remove all soil. The result is placed in a small dish with water and carefully examined under the microscope until no other (seed) species are found.
Common fruits include apples and pears, grapes, wild strawberries, raspberries, currants, plums, and cherries. Hazelnuts and walnuts are also common. Fruits that we hardly eat anymore, such as black mulberries and medlars, also surface in this way. Were these fruits only intended for consumption in the Middle Ages or did they also have other purposes?
“Many herbal books from the Middle Ages are known that state which fruit was used for what, such as the Cruijdeboeck by Rembert Dodoens (Rembertus Dodonaeus) from 1554,” says Van Haaster. “It says what was done with each species, complete with medical theories. A medicinal application has been written about every plant, but the question is whether they were actually used for it. Most of the fruits were probably just eaten.”
In addition to seeds of fruits, cesspools contain seeds of various types of weeds. Do these weeds also have medicinal properties? “According to Rembert Dodoens, yes”, smiles van Haaster. “But the strange thing is that many of these weeds are downright poisonous, such as the Bolderik. We have long wondered how these types of weeds ended up in cesspools. From historical sources we have discovered that these weeds were mostly field weeds and therefore grew on the land between the grain. They were taken during the harvest, eventually ending up in the bread that the people ate and thus in the cesspool. Poor people must have been crooked at night from the pain in their stomachs.”
Rich or poor?
The presence of certain seeds in cesspools can be an indication of wealth or poverty. Rich people used to eat food that was scarce, imported from distant lands, or simply expensive. Think pomegranates and pumpkins. Or spices such as pepper and cinnamon. Sounds logical, yet it is difficult to attribute 'rich' or 'poor' to a cesspool. Just as we now eat things for Christmas dinner that we don't eat throughout the year, poor people in the Middle Ages also sometimes jumped out of the band. For example, after Lent. For forty-six days, the Catholic Church allowed them to eat almost nothing, except on Sundays. After this period people ate more luxuriously to celebrate that the fasting period was over. For example, we sometimes find seeds of pomegranates in cesspools of poor people.
In addition, in the Middle Ages there was a market that traded in second-rate foodstuffs. It sometimes happened that spices came into contact with seawater during the crossing to our country and therefore got moldy. These spices were washed and sold at one tenth of the normal price. Broken cinnamon sticks and overripe fruits were also sold this way. Due to a small imperfection in the merchandise, prices plummeted. This made them available to those with less money. Unfortunately, today archaeobotanists can no longer determine whether the peppercorns were moldy or whether the pomegranates were overripe.
Diseases
As a child, Henk van Haaster (1959) liked to dig in the ground. If something was being dug somewhere, he was there like the chickens to see if they had not accidentally forgotten shards. After high school he went to study biology. When it turned out that biology almost didn't involve going into nature, as he had expected, he started taking as many geological and ecological courses as possible. “The metabolism of snails no longer interested me that much.” He eventually got a job as a freelance archaeobotanist at the University of Amsterdam. Together with a number of other archaeobotanists, he founded the company Biax (which stands for cross-pollination between Biology and Archaeology), an archaeological consultancy. Since then he has been working there as a specialist in the field of archaeobotany.
We also know from historical sources that people used to suffer from terrible diseases, for example, blood piss, consumption and the plague. All diseases caused by bacteria. We still know these diseases today, although they are now called differently. Pissing blood is a collective term for diseases caused by prostate and kidney problems. Tering is the same as what we now call tuberculosis. We still know the plague in its present form. Fortunately, this deadly disease is rare these days. Can diseases also be found in poop? “To a certain extent yes”, replies van Haaster. “For example, by eating contaminated meat, people could contract tapeworms and roundworms through contact with sick animals. We regularly find eggs of whipworms and roundworms in bear. This tells us about the health of the residents. So not good.”
Excavating cesspools is not always without risk. Some bacteria can survive for centuries, presenting a risk of contamination. Anthrax is a dangerous example of this. “We do not excavate cesspools younger than two hundred years,” says van Haaster. “We can only expose such a cesspool with sufficient precautions such as gloves.”
“It's actually strange that so little research has been done into people's eating patterns to date,” concludes Haaster. “From prehistoric times, the care of daily food has been one of the most important activities of man. Perhaps scientists will examine our poop in the future. Perhaps that's a good point to think about when you're back on your own cesspool and making a contribution to cultural history."