Did Romans use vomitoriums? Were chastity belts a thing? Does sugar cause hyperactivity? Does alcohol warm you up?
It’s Friday again, and like the last couple of Fridays, I’m on a household myth debunking mission. (You can read the previous installments here and here.)
There are dozens more on my to-do list, so let’s dispatch the next ten.
- The Great Wall of China is the only manmade structure visible from space
The Great Wall of China cannot be seen from any height that could reasonably be described as “space”. Even from the Kármán line (after Theodore von Kármán, who calculated a theoretical limit for aeroplane flight) of 100km above ground level, the Great Wall cannot be seen.
Can any other manmade structure be seen from space? Most certainly, yes. The Three Gorges Dam (the actual dam wall, not just the lake it holds back) can easily be seen from 100km altitude. In fact, it can faintly be made out from 500km altitude.
Dubai’s Palm Jumeirah, an artificial archipelago of islands, and the Dutch Afsluitdijk can both be seen from 1 000km above the Earth.
All large airports can be seen from an altitude of 100km, as can harbours, solar farms, large open-cast mines, and many bridges over wide rivers or bays. Farms aren’t structures, so although one can see them, they don’t really count.
One can just make out Cape Town’s harbour from 500km. At the same altitude, one can start to make out Johannesburg’s mine dumps, and at 100km they’re easily visible, as is Kimberley’s Big Hole, and you can just make out FNB Stadium. There are even some stretches of highway that are detectable from the Kármán line, such as the straight stretch of the N3 between Pietermaritzburg and Camperdown.
So, even if the Great Wall of China were visible from space, which it isn’t, it wouldn’t be the only manmade structure visible from space.
- 2. Vikings wore horned helmets
Imagine you’re a 9th-century raider, sailing across the seas to conquer or plunder. Now imagine wearing a helmet with massive horns on it while doing so.
You’d feel silly, wouldn’t you? The horns would get tangled in lines while aship, they’d get in the way while fighting, and the rest of the time they’d just make your helmet really heavy and unbalanced.
Vikings felt the same way. There isn’t even much evidence that Vikings wore helmets at all. Only one complete helmet has survived from the Viking era, and it didn’t have horns.
Never say never, though. There does exist a tapestry from the early Viking era on which horned helmets are depicted, and there are two human-like figures with long horns on the Golden Horns of Gallehus, so perhaps horns were sometimes part of ceremonial Viking practices.
Two helmets that once were thought to be Viking turned out to be much older. In the Bronze Age, depictions of horned helmets weren’t unique to Scandinavia, either, and probably got there via the sea-faring Phoenicians.
No contemporary sources ever mention Viking warriors with horned helmets. They were an invention of Carl Emil Doepler, who designed the costumes for Wagner’s opera Der Ring des Nibelungen in 1876. Original sketches can be seen here.
- 3. Alcohol warms you up when it’s cold
A cloaked stranger walking into an inn, stamping the snow off his boots, rubbing his hands and calling for a shot of whiskey to warm his bones, is a cliché.
According to legend, dogs named after Bernard of Menthon, who established a hospice atop the inhospitable Great St. Bernard Pass through the Alps between Italy and Switzerland, would carry little casks of brandy to help revive travellers trapped by blizzards or avalanches.
There is no truth to this legend, and while the monks of the St. Bernard Hospice will gladly sell you a cask, they deny that any St. Bernard mastiffs ever carried brandy casks on their collars.
That indelible “collective memory” originates with one of the most famous painters of animals of the Victorian age, Sir Edwin Landseer. A child prodigy, he painted Alpine Mastiffs Reanimating a Distressed Traveller in 1820, depicting a pair of St. Bernards attending to a trapped avalanche victim, one of them with a cask hanging from its collar. (See main illustration.)
In reality, strong alcohol can make you feel warm, but that’s deceptive. Alcohol is a vasodilator, so it sends warm blood to your skin, where you can feel the warmth. Blood near the surface of the body cools more quickly, though, so the net effect is that your core body temperature actually declines.
Worse, alcohol causes dehydration, which makes one more susceptible to hypothermia. It can lead to bad decisions in dangerous weather. And, as a central nervous system depressant, it can even send one to sleep in the cold, which can be lethal – though it is reputedly a pleasant way to die.
In short, alcohol makes your body colder, not warmer.
- 4. Eating gluten free is healthy
Many food retailers and restaurants label some of their offerings as gluten-free. There’s a widespread perception that, like vegetarian food, it is healthier to avoid gluten.
Gluten is a protein that occurs naturally in wheat, rye, barley, spelt, and some types of oats. As a consequence, it occurs in bread, pizzam and other baked goods, in beer, and also in some foods where gluten is used as a binder.
The notion that because gluten is bad for some people – that is, people with coeliac disease or a non-coeliac gluten intolerance – it must be better to avoid gluten even if you don’t suffer from these conditions, is untrue, however.
“There is no compelling evidence that a gluten-free diet will improve health or prevent disease if you don’t have celiac disease and can eat gluten without trouble,” says the Harvard Medical School.
In fact, people who avoid gluten could miss out on nutrients like folic acid and iron, risk insufficient fibre in their diet. Many gluten-free foods contain more sugar and fat than their ordinary counterparts. Instead of weight loss, a gluten-free diet often leads to weight gain.
Avoiding gluten also risks killing off the microbes that help to digest gluten, which can cause gluten intolerance if you later add gluten back to your diet.
Not being able to process gluten is a medical condition. It isn’t healthy, and shouldn’t be fashionable, to avoid gluten if you don’t have a medical reason for doing so.
- 5. Feed a cold, starve a fever
This particular bit of popular wisdom dates back to 1574, when a lexicographer named John Withals wrote: “fasting is a great remedy of fever”. Withals was not a doctor. He also predated a fairly significant amount of modern medical science.
In fact, when you have a fever, your metabolism speeds up, burning more calories, and requiring more food. By denying your body food, you’re weakening its ability to mount a vigorous immune response.
Any viral infection can cause a fever, and that includes the rhinoviruses that cause the common cold. Distinguishing between a cold and a fever is, therefore, nonsensical.
If whatever ails you leaves you with no appetite, it’s not a crisis, unless you are already undernourished. However, it is better to try to eat something when you’re ill, and you should always take in lots of liquids.
On the upside, “the traditional bowl of chicken soup (or even plain broth) remains the gold standard when it comes to eating while sick,” say the experts.
- 6. You need eight glasses of water a day
How big is your glass? In backward countries that refuse to give up on the incomprehensible weights and measures that the British Empire bequeathed them, they talk about the “eight-by-eight” rule. That is, you need to drink eight glasses of eight ounces each, per day.
Eight fluid ounces amount to 227ml, so eight glasses worth is roughly 1.8 litres of water.
The US National Academies of Sciences, Engineering and Medicine actually recommend that you drink much more: 3.7 litres for men, and 2.7 litres for women. Of this, about 20% would come from food, and the rest from liquids.
How much water you need depends on a lot of things. If you’re large, you’ll need more water. If you’re sedentary and live in a cool climate, you need less water than if you’re active in a hot climate. If you drink alcohol, you’ll need more water.
The correct answer to how much water you should drink is: it depends.
Drink when you’re thirsty. Recognise the signs of mild dehydration: headaches, fatigue, low mood, and dark or cloudy urine. Drink more when it’s hot, or when you’re exercising. If you exercise a lot, take care not to overdo the water. Instead, switch to a drink that replenishes electrolytes. If your pee is clear or light yellow, you’re fine.
Who counts glasses of water anyway?
- 7. Chastity belts were used during the Crusades to prevent adultery
What is a knight, bravely riding forth to defend his religion’s holy sites from people of other religions who consider them equally holy, to do with the defenceless young wife he leaves at home? Surely, in the absence of a marital duty provider, the poor lass will be overcome with lust, or, if not, be ravished by the neighbours?
According to legend, the local blacksmith would ride to the rescue with a contraption designed to be locked around the nethers that prevents intercourse but permits waste elimination. The lonely grass widow would wear this for months, or years, until her husband returned.
The historic record shows a sketch of such a device in Konrad Kyeser von Eichstätt’s Bellifortis, published in 1405.
If this myth were true, however, the historical record would be replete with accounts of women who died as a result of infections caused by chafing and the inability to maintain proper hygiene. Not a single such account exists.
Picking mediaeval locks was also not a particularly challenging task.
Men would surely document, among the expenses of their martial campaigns, an expensive, custom-made metal contraption for their wives. Metal armour was rare, and costly to make.
Chaucer would have had a field day with such a licentious article, but he remained mum on chastity belts.
Finally, some of these devices would have survived the years, and come to us via archaeology.
In truth, the early references to such devices were likely attempts at humour, and alleged archaeological examples are believed to be Victorian-era fakes, made as jokes or for prurient sensationalism.
That there’s no reliable evidence of chastity belts during the Middle Ages doesn’t mean they weren’t eventually invented, of course.
There’s evidence that they were used in the 18th and 19th centuries.
They weren’t worn all the time, of course, for reasons already discussed. In some cases, they were used for a defensive purpose, including by men in prisons. The majority of chastity belts were used as anti-masturbation devices, however.
Until as recently as the early 20th century, it was widely believed that solo pleasures were sinful, physically harmful, and/or the cause of mental illness. Patent records exist of devices to restrain both boys and girls from playing with themselves.
Today, chastity belts are limited to the kink community, where their purpose is openly discussed and subject to negotiated consent. They’ll always be a reminder of the dirty minds of Victorians, though.
- 8. Glass is a liquid
If you’ve ever toured a mediaeval cathedral or other historic building with very old glass in the windows, you might have heard a tour guide explaining that the glass is thicker at the bottom than at the top because glass is liquid, and it is very slowly flowing downhill.
If you haven’t, you might have heard a school chemistry teacher say the same.
The tour guide, and that teacher, are full of it, though.
It’s a cool story, but it isn’t true. Glass isn’t quite a solid, though. It is known as an amorphous solid, which is a solid without a defined crystalline structure. The exact chemistry of amorphous solids, which are solid at the low end of a temperature range, and malleable or rubbery at the high end, is complicated. Some of the details fall under the unsolved problems of physics.
While the molecules in glass can move, this movement does not explain the thickening of very old glass panes. Some glass that is much older does not exhibit this defect, and mathematical analysis suggests that for glass to flow sufficiently far to create the cathedral glass effect at ambient temperatures would take billions of years.
The reason old panes are imperfect is because they weren’t made perfect. The glass was blown, and then cut and flattened, leaving them with uneven thickness and other imperfections.
Masons who installed such glass usually preferred to put the thicker side on the bottom. The glass didn’t flow; the panes looked like that from the start.
A different mediaeval technique resulted in circular-looking crown glass panes. Although glass-making processes improved from the 17th century onwards, it wouldn’t be until the invention of float glass in the mid-20th century that we’d get the perfectly flat glass we take for granted today.
- 9. Romans used a vomitorium to purge after overeating
The term inflames the imagination. The ancient Romans had vomitoria. They were also known for decadent toga parties and bacchanals and elaborate feasts. Surely, the two must be connected?
Legends of over-eating Romans who would, between courses, betake themselves to an adjacent vomitorium, complete with basins and a means to tickle the back of the throat, arose. Bulimia has never looked so, well, classical.
In fact, the word vomitorium, while it does come from the verb for “to spew” or “to spew forth”, refers to the entrance of a stadium or amphitheatre, through which a large crowd would spew forth after an event. Sickening, isn’t it?
- 10. Sugar causes hyperactivity in children
All it takes to start a widely accepted myth is a single paper that observes a single child in a single experiment. That is how thin the evidence is that sugar causes children to be hyperactive.
All research since that paper, published in the 1970s, has found no clear connection between children’s sugar consumption, and hyperactivity.
They did find, however, that parents who thought their children had consumed sugar rated them as more hyperactive, even if they had taken a placebo.
Children generally get sweet treats on festive occasions. They’re with friends or family, it might be a holiday, but whatever the case, they have reason to be naturally excited and full of vim and vigour. The sugar isn’t the cause of their active behaviour; all the other excitement and adrenalin is.
Of course, excessive sugar consumption does lead to weight gain, and it also reduces appetite for other, healthier foods. The recommended daily intake of sugar for children is quite low: at 25 grams, it is equivalent to just one candy bar, or a little less than a single soft drink. That said, such limits are usually set very conservatively, so a little more probably won’t hurt them, provided they get a balanced diet and a healthy amount of exercise.
There’s good reason to limit the sugar intake of children, but hyperactivity isn’t one of them.
The views of the writer are not necessarily the views of the Daily Friend or the IRR.
If you like what you have just read, support the Daily Friend
Image: Alpine Mastiffs Reanimating a Distressed Traveler, by Sir Edwin Landseer, 1820. Public domain.