Wellcome Trust, Wikimedia Commons // CC BY 4.0
Wellcome Trust, Wikimedia Commons // CC BY 4.0

Fascinatingly Filthy: How Bad Science Saved Lives in Victorian London

Wellcome Trust, Wikimedia Commons // CC BY 4.0
Wellcome Trust, Wikimedia Commons // CC BY 4.0

If you’re a fan of science or history, you know that many of the most important discoveries in medicine were made due to wild speculation, lazy lab techs, or plain old accidents. And plenty of theories of healing were so wrong as to have actually been responsible for deaths, not cures. 

But every once in a while, humans of the past got lucky: Even though their science was completely wrong, the theory driving it saved lives anyway. Such is the case with “miasma,” a concept popular throughout the mid-1800s with laypeople, doctors, and public-health advocates.  

“The prevailing view was that ‘miasma’—foul smell, particularly the stench of rotting matter—was the cause of disease. It was an appealing idea—not least because the slums, where epidemics raged, stank,” says Lee Jackson, author of Dirty Old London, which recently came out in paperback. 

Mental_floss spoke to Jackson about how attempts to clean up the unbelievably filthy city in the 19th century—when the population increased tremendously—led to major improvements in both public and personal health that had a lasting legacy around the world. And it all happened despite the fact they didn’t have the science right. 

THE STENCH OF DISEASE

The true cause of disease—germs, or pathogens—wasn’t verified until Louis Pasteur conducted his experiments of the 1860s (though some scientists had proposed the idea much earlier), and it was another decade before the bacteria that cause tuberculosis, cholera, dysentery, leprosy, diphtheria, and other illnesses were identified and understood.

The Victorians made the classic error that correlation equals causation. Slums smell, due to poor sanitation, piles of garbage stacking up, and the lack of bathing and clothes-washing facilities; people in slums die of epidemics at a faster rate; ergo, stench causes disease.

And boy, did London stink. 

Let’s start with the dead bodies, which were buried in churchyards, most of them in the middle of neighborhoods. “Coffins were stacked one atop the other in 20-foot-deep shafts, the topmost mere inches from the surface. Putrefying bodies were frequently disturbed, dismembered or destroyed to make room for newcomers. Disinterred bones, dropped by neglectful gravediggers, lay scattered amidst tombstones; smashed coffins were sold to the poor for firewood,” Jackson writes in Dirty Old London.  

As the bodies, dead from old age or disease, rotted, pathogens leaked into the water table, sometimes making their way to nearby wells. But since germ theory wasn’t understood, it was the stench of the near-surface bodies that got the attention.

“London’s small churchyards were so ridiculously full, that decaying corpses were near to the top soil; ‘graveyard gases’ were a familiar aroma. In fact, gases from corpses are relatively harmless,” Jackson says. Large, open, park-like cemeteries were soon built on the outskirts of the city, relieving “miasma” and live bacteria from close proximity to drinking water. 

Sewage was another disease vector that seems obvious to the modern person, but to the people of the past, it was the gag-worthy smells wafting from privies that caused disease. In poor areas, up to 15 families—whole tenements—might be sharing one overflowing shack. Slumlords liked to cut corners by refusing to have the “night-soil men” come by for a pick-up; these workers would shovel the waste into buckets and haul it out to farms to be used as fertilizer, and they (understandably!) didn’t work for free. 

But sewage wasn't just a problem for those actually using the privies; the liquid that leaked into the water table from the privies also spread disease. Even in middle-class homes, solid waste accumulated in basement cesspools that slowly leaked liquid wastes into wells just feet away. 

“The building of a unified network of sewers in the 1850s–'70s undoubtedly saved London from further epidemics of cholera and typhoid. It was done on grounds of ‘miasma’ but, regardless, the consequences were very positive,” Jackson says. 

CLEANING UP THE CITY

Public toilets were also finally built in the latter part of the 1800s, which cut down on street-stink—and also allowed women to have more freedom. Because only the poorest women and prostitutes peed in public (usually crouching over sewer grates to do so), lack of public facilities meant working-class women were often in a bind. These women “didn’t go out, or didn’t go’” according to Jackson’s research. “Navigating the city, therefore, required some level of planning, depending on your social class and whether you considered yourself ‘respectable’” Jackson says. (Like today, the bathrooms of shops or restaurants were generally only available to those making a purchase.)

Providing a place to pee also had the positive effect of cutting down on public urination by men. In some places the odor of urine, both fresh and old, was so intense that complaints to local councils were constant from the people who lived nearby. In some cases, the urine even degraded structures over time. Smart property owners installed “urine deflectors” on the sides of their buildings—if you were to aim your stream there, it would get bounced back onto your shoes. 

Public bathhouses—which often included spaces to wash and even dry laundry—also proved to be a boon to public health. It wasn't just about keeping bodies cleaner; for the poorest people in the city of London, water was only available from a public pump, and washing clothes and linens was often difficult-to-impossible. A place that allowed for washing of both body and textiles meant that diseases spread by fleas (such as typhus) were reduced. Bonus: Everyone smelled a bit better too.

Victorians went after that which stank—and public health improved. As Ruth Goodman writes in her book, How to Be a Victorian, “Housework was valuable in preserving health whichever theory you ascribed to. So too was community cleanliness: germs could be fought effectively as miasmas by good town management of waste, by regular street cleaning, by prosecuting those who dumped waste in public areas. Personal hygiene also had value with both germ and miasma theories of disease.” 

The Victorian era is now known as a great era of sanitation in Great Britain, with lasting changes and public infrastructure that still exists today. In a sense, it matters little that it was all based on something that didn’t exist.

nextArticle.image_alt|e
NOAA Photo Library, Flickr // CC BY 2.0
7 Impressive Animal Defense Mechanisms
NOAA Photo Library, Flickr // CC BY 2.0
NOAA Photo Library, Flickr // CC BY 2.0

The deep-sea squid known as Octopoteuthis deletron has a startling defense mechanism: When threatened, the squid attacks its predator and then pulls away, breaking off the tip of its own arm and leaving it behind as a diversion. As the arm continues to glow and twitch, the squid makes its escape.

But this squid isn't the only creature with a bizarre tactic for keeping itself alive. Here are several other animals with impressive defense mechanisms.

1. THE LIZARD THAT SHOOTS BLOOD FROM ITS EYES

The Texas Horned Lizard is a scary-looking creature. Brown, plump and perfectly camouflaged in its native sandy environment, its first line of defense is its spiky demeanor. If the sharp spikes and horns don't ward off predators, the lizard steps it up a notch and squirts a well-aimed stream of blood out of its eyes. The stream of blood, which can go as far as 5 feet, is mixed with a foul-tasting chemical that wards off predators. But this odd weapon comes at a cost: The lizard may release one-third of its total blood supply this way, amounting to 2 percent of its body mass. Unfortunately, its population numbers are dropping thanks to a threat that won't retreat after a well-aimed squirt: habitat loss due to rapid urbanization in the Lone Star State. 

2. THE HAIRY FROG THAT BREAKS ITS OWN BONES

Trichobatrachus robustus, aka hairy or horror frog

Emőke Dénes, Wikimedia Commons // CC BY-SA 4.0

What if every time you felt threatened, your first and only method of defense was to break your own bones and use them for weapons? Meet the hairy frog, a Central African species. When breeding, the male frogs develop thin strands of skin along the sides of their bodies that resemble hair. In theory, these strands also allow the frogs to take in more oxygen while they watch over their eggs. But what's really compelling about this frog is its ability to crack its own toe bones and push them through their skin to form sharp claws, which are great for warding off would-be attackers.

While it's not completely clear what happens to the bones after the threat of attack subsides, researchers believe the bones slide back under the skin when the frog's muscles relax.

3. THE NEWT THAT TURNS ITS RIBS INTO SPIKES

spanish ribbed newt

The hairy frog isn't the only amphibian that uses its bones for weapons. When attacked, the Spanish ribbed newt shifts its ribs forward at an angle and pushes them through its stretched skin. The resulting effect is a row of spikes on either side of its body. Like the hairy frog, the newt has to force the bones through its skin every time it is attacked, but the mechanism seems to cause little or no harm to the creature. Maybe one day it'll get its own robot protector: A team of researchers at the the Swiss university EPFL created a robotic salamander inspired by the newt, which they called the Pleurobot (after its scientific name, Pleurodeles waltl).

4. THE TERMITE THAT BLOWS ITSELF UP

Talk about taking one for the team. When under attack, a species of termites found in the French Guiana rain forests sends older worker bugs on suicide missions to defend the whole colony. These older bugs, no longer as useful to the pack as they once were, come equipped with "explosive backpacks" that, over a lifetime, fill with toxic crystals produced by glands in the abdomen. When mixed with salivary gland secretions, these crystals create a toxic liquid that explodes on enemies, paralyzing them and killing the worker at the same time. These termites aren't alone among insects in using a suicidal defensive tactic: When faced with a threat, an ant found in Borneo expands its abdomen until it ruptures, shooting out a toxic liquid

5. THE FISH THAT SLIMES ITS ENEMIES

Hagfish are eel-shaped marine animals with the incredibly useful ability to slime their enemies. When threatened, the hagfish emit a slime from their pores that, when mixed with water, expands into a gelatinous goo that can either trap predators or suffocate them by clogging their gills. The video above shows a hagfish being attacked 14 separate times by sharks and other big fish, and coming out completely unharmed. Each predator took one bite before immediately spitting the hagfish out and swimming away, gagging. The best time to encounter a hagfish is probably after it's emptied its slime glands withstanding such an onslaught; the glands take three to four weeks to refill.

6. THE SEA CUCUMBER THAT SHOOTS ORGANS OUT OF ITS ANUS

sea cucumber on coral reef
iStock

Sea cucumbers can seem pretty boring. There are some 1250 known species of these sedentary creatures in the world, and many of them do indeed look like cucumbers. But when it comes to survival, things get interesting. Like starfish and sea urchins, sea cucumbers are echinoderms, and they can regenerate lost body parts if necessary. This comes in handy when they're threatened. The sea cucumber will expel its internal organs, which are sticky and sometimes contain a toxic chemical that can kill predators. They don't have much of a defense against pollution though, which is a problem, because they're superstar ocean-floor cleaners.

7. THE OPOSSUM THAT PLAYS DEAD

possum playing dead in the grass
Tony Alter, Flickr // CC BY 2.0

You can't do a roundup like this without at least mentioning the opossum. We typically refer to this creature's infamous defense mechanism as "playing dead," but there's actually nothing playful about it; the act is completely involuntary. Under intense fear, opossums fall into a comatose-like state that can last for hours, long enough to convince any predator that the opossum is already dead. Also unappetizing: Fear causes these animals to emit a corpse-like smell that only adds to their act. Thank the opossum for providing some defense for us too: They eat venomous snakes and ticks, gobbling up to 4000 insects a week.

nextArticle.image_alt|e
Hans Hillewaert, Wikimedia Commons // CC BY-SA 4.03
10 Body-Snatching Parasites
Hans Hillewaert, Wikimedia Commons // CC BY-SA 4.03
Hans Hillewaert, Wikimedia Commons // CC BY-SA 4.03

There are a lot of parasites out there. Some estimates suggest that as many as half of all the species on earth live inside—and feed off—other species. One new study published online (which hasn't been peer reviewed yet) argues that the parasitoid wasps might be the largest single group of animals—a title generally thought to be held by beetles.

Practically every species has its own set of parasites, and even parasites have parasites. In many cases, a parasite's host is little more than a habitat where it can eat and breed. But some parasites have gone a step further, evolving ways to manipulate their hosts in ways that give the parasite a better shot at growing up and spreading its young far and wide. Their methods can be as deliciously gross as the worst imaginings of horror movie screenwriters. Here are 10 examples to inspire new terrors of the silver screen.

1. JEWEL WASP // AUSTRALIA, PACIFIC ISLANDS


The jewel wasp Ampulex compressa is iridescently beautiful, but it's a nightmare for the American cockroach. When a pregnant female wasp gets hold of a roach, she temporarily paralyzes its muscles with a sting, then threads her stinger up into the roach's brain, injecting a cocktail of chemicals that turn the roach into a zombie. The roach could move when the paralysis wears off, but now it doesn't want to. Instead, it allows the wasp to gently lead it by one antenna to her burrow, where she walls it in with one of her eggs. That egg will soon become a larvae that spends its first week on earth eating the living roach bit by bit before pupating and emerging as a wasp to continue the cycle.

2. NEMATOMORPH HAIRWORM // EUROPE

Everything seems normal for weeks after a long-horned grasshopper has drunk water containing the microscopic larvae of the hairworm Spinochordodes tellinii, but that changes as soon as the worm grows big enough to start yearning for a mate. That's when it secretes chemicals that change its host's brain chemistry, making deep water seem enticing to the insect. The grasshopper suddenly has a suicidal urge to take a long hop off a short pier, and as it drowns, the worm—now as much as three times as long as the insect it lived in—squeezes out of its host and swims off to find a mate. Other hairworm species prefer praying mantises or spiders as hosts, but it's the same endgame for them all.

3. PARASITIC BARNACLE // MARINE COASTS

Sacculina carcini
John Aplessed, Wikimedia Commons // Public Domain

A female Sacculina carcini starts its life like any other barnacle—as a tiny planktonic baby floating free in the ocean. But unlike your average barnacle, when she drifts onto a crab she doesn't just settle down and become a warty bump riding on its shell. Instead, she burrows into the crab and grows until she infiltrates every crevice of the crab's body. This can take years, but eventually she's big enough to inflate her bulbous reproductive structures through the crab's abdomen so microscopic males of her species can fertilize her eggs. Once that happens, her crabby host stops molting and growing; all it does is eat and take care of its parasite. Her babies are incubated inside the crab's abdomen, and since part of her is inside the crab's brain by now, she also hijacks its egg-caring behaviors—even male crabs nurture them—to aerate and disperse thousands of her own future mind-controlling brood.

4. ICHNEUMOID WASP // NORTH AMERICA

ichneumoid wasp
MirandaKate, Flickr // CC BY-NC 2.0

A female ichneumoid wasp Campoletis sonorensis sneaking up on a grazing caterpillar isn't looking for a meal for herself—she's shopping for a nose-to-tail larder for her young. The wasp injects one or two fertilized eggs under the caterpillar's skin, and just for good measure, squirts in a virus that will keep the caterpillar's immune system from attacking the invaders. When she flies away, the caterpillar goes right back to eating, but it's a dead grub walking: In a few days, the wormlike wasp larvae hatch inside the caterpillar. They'll spend a couple of weeks munching away at its guts until they grow large enough to burst through its body wall. Then, they spin cocoons—often beside or on the dead body of their host—and pupate into another generation of chest-busting parasitoids (which, unlike most parasites, always kill their hosts).

5. GREEN-BANDED BROODSAC FLATWORM // EUROPE AND NORTH AMERICA

A land snail's eyestalks are normally a pretty drab affair, but that all changes if the snail licks up bird droppings infected with larvae from the flatworm Leucochloridium paradoxum. The baby worms move into the snail's digestive gland, forming an asexual colony that can eventually make up a quarter of the snail's mass. As the colony matures, it starts packing members into bright green, squirming brood sacs that writhe up into the snail's eyestalks, swelling them into fat approximations of wriggling caterpillars. If that's not enough to grab a hungry bird's attention, those pulsing, writhing brood sacs can also break through the snail's body wall and crawl off to mimic a juicy grub on their own.

6. PHRONIMA AMPHIPOD // DEEP OCEAN WORLDWIDE


Freshwater and Marine Image Bank, Wikimedia Commons // Public Domain

The deep-sea amphipod genus Phronima is a literal body-snatcher. This parasitoid captures gelatinous salps—jet-propelled, filter-feeding planktonic animals that are closely related to vertebrates—and hollows them out with jaws and claws, consuming the salp's brain, gills, stomach, and muscles, and scraping its inner walls smooth. The salp body—technically still living—becomes a barrel-shaped, ocean-going home that the amphipod can maneuver like a miniature submarine. It might eventually be a full house, too—female Phronima keep their young in the barrel and care for them until they've grown.

7. RIBEIROIAN TREMATODE FLATWORM // NORTH AMERICA

deformed pacific chorus frog infected with ribeiroia ondatrae parasite
Brett A. Goodman, Pieter T. J. Johnson, Wikimedia Commons // CC BY 2.5

The horror starts when larvae of the parasitic flatworm Ribeiroia ondatrae leave the snail they used as a nursery and burrow into the tail of a bullfrog tadpole. When the tadpole metamorphoses into an adult frog—a period of time that varies between species—the flatworms form cysts around its developing legs, disrupting their growth in ways that damage or double them. The crippled, flatworm-infested frog can't jump away from predatory birds like herons, which gobble them up. The flatworm then spreads to new waterways wherever the bird poops.

8. GALL WASP // WORLDWIDE

gall wasp eggs
Justin 0 of 0, Flickr // CC BY-NC 2.0

Not even plants are safe from parasitism. Females of Cynipidae, the family of gall wasps, lay their eggs inside leaves or under bark, and their larvae make the plant cells surrounding them grow faster than they would normally, effectively forcing the plant to grow them a house. Weird, nonleafy shapes rise up out of the plant, filled with juicy nutritious tissues that feed the wasp larvae and surrounded by tough woody walls that protect it until it becomes an adult (more than a year in some species) and chews its way out of its safe space.

9. ENTOMOPATHOGENIC FUNGUS // NORTH AMERICA

goldenrod beetle infected by mind-controlling E. lampyridarum fungus
Steinkraus et al. in Journal of Invertebrate Pathology, 2017

Goldenrod soldier beetles depend on the family of flowering plants commonly known as asters, which includes goldenrods and daisies. The beetles eat the plants' pollen and mate in their shade. But if a beetle gets infected with the fungus Eryniopsis lampyridarum, it climbs up an aster's stem, clenches the base of a flower with its mandibles, and dies. Within a day, the fungus forces the dead beetle's wings open to expose its spores, which rain down on the hapless beetles below.

10. OPECOELID TREMATODE FLATWORM // PACIFIC MARINE REEFS

Coral colony infected by trematode Podocotyloides stenometra
Alamy

The tiny polyps that build stony corals are usually an inconspicuous brown. But that changes whenever a polyp inadvertently grabs a young Podocotyloides stenometra flatworm for a meal. Somehow, the trematode worm doesn't get digested—instead, it invades the polyp's tentacles, swelling them and turning them bright pink. The color is a bright billboard advertising deliciousness to butterflyfish on the reef, who eat the flashy polyps and spread the worm to other corals across the reef.

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios