Fun fact: The patient was dead.

You see, famous German physician and future Nobel laureate Robert Koch had just discovered the actual bacterium that causes cholera. But Pettenkofer suspected that the bacterium alone wouldn't cause cholera; he believed that other environmental conditions had to be in place for the disease to really make an impact. He noticed that the people who came down with cholera weren't just coming into contact with the disease -- they also rarely washed, had poor hygiene and drank filthy groundwater. Pettenkofer was a hygienist, after all, and basically was using the whole cholera experiment as a way of suggesting to people, "Hey, let's just try being less shitty, in general." He named his little adventure his "experimentum crucis," wisely leaving room for a sequel, Experimentum 2: Crucis Control, should the original do well in the scientific community.

After downing the cholera cocktail, Pettenkofer began to get violently ill within a day (SURPRISE!). However, the tough bastard never came down with a full-blown case of cholera. While experts today interpret his symptoms as having been a mild case of the disease, at the time Pettenkofer thought his experience was a pretty successful "FUCK YOU!" to Koch and his supporters and certainly a strong case for his "Let's Be Cleaner and Less Shitty" argument.

Via ihm.nlm.nih.gov
Pettenkofer: Equal parts Hemingway and the more horrifying aspects of what they make you do in hell.

Koch's theory eventually won out. But people thought that Pettenkofer was probably on to something with the whole "Hey, maybe we shouldn't drink the groundwater?" thing. He ended up on a stamp. So, if you want to be immortalized on a stamp, you know ... drink cholera? There's not really a good lesson to pull from this experiment.

Some of Head's most important research involved slicing open his own arm, severing its nerves and tracking the slow return of sensation over the course of years.

Via Bartsandthelondon.nhs.uk
Redacted: Raging nutjob.

Head observed that patients with peripheral nerve damage could experience their sensation of touch returning gradually over time. However, because the only data were patients' experiences, and since these patients could not articulate their experiences in detailed medical jargon, Head found it difficult to track their recoveries in a consistent, reliable way.

As he put it, "It soon became obvious that many observed facts would remain inexplicable without experimentation carried out more carefully and for a longer period than was possible with a patient, however willing, whose ultimate object in submitting himself to observation is the cure of his disease."

Via Jnnp.bmj.com
In other words, "They don't want to be experimented on -- they want to be fucking healed."

And even though it could be argued that, as a doctor, curing the disease should also have been his only goal, Dr. Head had other plans. Crazy plans. Head had another physician cut open his left arm in order to sever its radial and external nerves. He then tracked his experiences for the next five years ("Hey, my patients were right after all; this does hurt like a son of a bitch!"). Between 1903 and 1907 Head had 167 examinations with his physician colleague Dr. W.H.R. Rivers, each lasting many hours.

During the examinations, Head would look away as Rivers would systematically apply various forms of pressure and temperature all over his arm, mapping out what (if anything) Head would report feeling. The probing tools ranged from the puppy-dog-tail-esque (e.g. cotton wool) to something straight out of Mordor (e.g. the tip of a soldering iron).

Via Elcomandodelamor.blogspot.com
"Ah, FUCK, it hurts! Why did I think it wouldn't?!"

Through his research, Head established two anatomically separate sympathetic nervous systems, "protopathic" and "epicritic," which regenerate at different rates following injury. The protopathic system is all-or-nothing (you can feel whether something is touching you, but you can't tell exactly where or with how much pressure), whereas the epicritic system is more sensitive (it is responsible for how we normally experience touch).

Now, here's where it gets weird.

Head's discovery of these separate nervous systems fit nicely with contemporary evolutionary theories about the human nervous system having separate primitive and more developed functions. Which was nice and all, but didn't really teach us anything new; it just confirmed other theories. So, Rivers notched up experimentation on this theory to frat house proportions, when he poked the tip of Head's penis with a needle and repeatedly dipped it into water that alternated between cold and scalding hot.

Via Wikimedia Commons
Which did wonders for his marriage, as you can tell from their uncontainable excitement in this picture.

Head experienced a great deal of pain (duh) but, unlike every other part of his body, the pain at the tip of his penis (called the "glans") more resembled the protopathic (all-or-nothing) sensations he experienced in his left arm when the nerves were severed. This made good evolutionary sense to Rivers insofar as the male sexual anatomy would be expectedly less neuroanatomically evolved than the rest of the body.

And that's where the term "dickhead" came from.

You see, it was discovered "the hard way" that, above 35,000 feet, pilots who had to eject from planes would pass out because of the lack of oxygen.

It's 1943, during WWII. As part of a set of experiments to study new oxygen equipment, Lovelace bails out of a B-17 bomber at over 40,000 feet. He is knocked unconscious when the parachute opens, and gets frostbite on one of his hands after his glove is torn away. So he just floats, unconscious, down to the ground, and for this experiment, he is awarded the Distinguished Flying Cross. And that's how we learned that we need to develop oxygen masks for high-altitude flights.

Via Stratocat.com
Other experiments included "Don't forget your parachute" and "You'll need a plane."

That's a lesson, it should be pointed out, that didn't warrant an additional experiment by a scientist. Lovelace watched wave after wave of pilots jump out of a plane at 35,000 feet and lose consciousness, and instead of immediately concluding "We should develop oxygen masks," he said, "Bullshit, those World War II-era fighter pilots are a bunch of pussies. This job calls for a motherfucking scientist." It was only after he jumped out of a plane himself that he accepted the previous pilots' lack of consciousness. Still not sure if that makes him the best or worst scientist in the world, but the bottom line is that we're terrified of him.

Via Dspace.lrri.org
He went on to work for NASA, though, probably as a rocket puncher.

Sanctorius built a large, elaborate scale and meticulously weighed himself, everything he ate or drank and all of his bodily waste. By comparatively weighing what he ate and drank with what he pooped and peed, he noticed that what came out was less than what went in.

To account for the leftover, Sanctorius came up with the theory of "insensible perspiration," a process whereby perspiration sneaks its way out of the body via pores and evaporates before we can perceive it as moisture by the skin. His study paved the way for the modern understandings of metabolism, not to mention the impact it had on the field of poop-weighing.

Via ar.utmb.edu
"Hey, my poop weighs LESS than my Hot Pocket! Is anyone LISTENING TO ME?!"

Through his passion with measurement, Sanctorius challenged medical theory of his day, which described the body in terms of Aristotle's theory of "humours" or essences. San-San proposed a more mechanical view of the body; that it was like a clock with interlocking parts. In 1614 he published a treatise called "On Medical Measurement," which was essentially the first ever study of what we now call basal metabolism.

His work is still admired and appreciated by modern scientists, and he even swayed most of his peers, which is probably the first time the "Hey, I just spent the last 30 years measuring my own shit, so you can trust me" argument actually worked.

Photos.com
Which could also get him credited for the invention of this facial expression.

If the scientist who drank cholera to prove how crazy he was and the scientist who burned his own penis to prove how badass he was somehow had an awful, awful baby, it would probably be John Hunter. Hunter (1728-1793) was a famous physician in England. His patients included Benjamin Franklin, Adam Smith and Lord Byron, and he was the personal surgeon to King George III. Other patients include his penis.

When Hunter was practicing medicine, London was a growing urban center, which (as is the case with most expanding cultures) meant that it was rife with prostitution. Some records suggest that there was one prostitute for every 27 men. Ben Franklin once famously quipped, "An apple a day keeps HOLY SHIT THAT'S A LOT OF PROSTITUTES." It was definitely a venereal disease sort of party, is our point.

Photos.com
"Damn, baby, I think I just discovered electricity. In my pants."

Obviously, Hunter came into contact with a lot of patients who were just silly with venereal diseases. Although it was well-established that venereal diseases were sexually transmitted, nobody really understood their courses or how they were related to each other. At the time there were two main divisions of venereal disease, clap (gonorrhea) and pox (syphilis). Gonorrhea was definitely not fun (it caused terribly painful urination, for example), but it was relatively common and not life-threatening. Syphilis, on the other hand, was much more serious, causing pervasive wart-like sores, fever, swollen lymph nodes and in its later stages blindness and damage to the brain, heart, liver and bones. Having encountered many different patients with both diseases, Hunter had hypothesized that two diseases can't occur in one body at the same time. He argued that clap and pox were in fact the same disease, just at different stages. A certain bodily "poison" caused the gonorrhea, which manifested in the genitals, and when that same poison spread to the rest of the body, the result was syphilis.

But how to prove this fine claim? Well, Hunter decided to inoculate with gonorrhea somebody who had never shown symptoms of either. He reasoned that if such a person developed gonorrhea (which he had already established would clear up on its own) and never developed any symptoms of syphilis, then it would be clear that they were separate diseases. His theory, of course, was that the previously clean test subject, after getting the gonorrhea injection, would in fact contract syphilis as well, thus proving his theory.

Photos.com
"It'll be like finger-painting. With diseases as paint and genitalia as fingers."

It's a simple concept but, for it to work, Hunter had to find somebody who he knew with mathematical certainty had never shown signs of either gonorrhea or syphilis. And since scientists are apparently a notoriously untrusting bunch, he decided to experiment on himself. Hunter made incisions on his own penis and inserted a bunch of infected pus from one of his gonorrhea-stricken patients, and that's the worst sentence we've ever published on this website.

Hunter obviously contracted gonorrhea, and then a few weeks later, a syphilis pox nodule did in fact appear on Hunter's penis! It was later named the Hunterian Chancre, which in no way makes injecting poison into your dick worth it.

Via Marshall.edu
Hunter's seminal (hee hee) treatise on venereal disease.

But hey, that proves that gonorrhea and syphilis are caused by the same poison, right? They're the same disease. Hunter was right!

Except actually he completely fucking wasn't, because modern medicine has shown that they are entirely different, separate diseases. So he was crazy and wrong?

The problem was that the gonorrhea sample that Hunter used to inoculate himself with came from a patient who was, in fact, suffering from both gonorrhea AND syphilis, he just didn't know it yet. So he accidentally took two diseases from a guy, injected them straight into his dick, drew the wrong conclusion based on the results and managed to "set back medical progress in terms of the understanding of medical diseases for half a century."

But at least someone named a pus-filled, red dick pox after him. That's kind of something, right?

Via Marshall.edu
Even seeing this picture of him makes us want to clean our monitors with rubbing alcohol.

Oh man. Oh man. Sorry, we're excited. We just love introducing our readers to brand new badasses, because we know how much you love them. J.B.S. Haldane (1892-1964) was a British geneticist and biologist. In the 1920s, Haldane wrote a number of influential and popular essays on genetics and evolution. He helped developed the field of population genetics. And he's what happens when science tries to make its own Teddy Roosevelt.

Via Wikipedia
Boom.

He was cultured, large, fearless and outspoken, he had a sick mustache and his list of accomplishments reads like a Bill Brasky sketch. According to rumor, one time "he drank quantities of hydrochloric acid to observe its effects on muscle action; another time he exercised to exhaustion while measuring carbon dioxide pressures in his lungs." He'd submerge himself in ice and breathe in carbon dioxide at the same time just to see what it was like. He wasn't even replicating an actual scenario someone might conceivably go through, he clearly just got bored and felt like doing something stupid. He fought in WWI (fucking loved it), and his commanding officer called him "the bravest and dirtiest officer in my army."

When he was tasked with helping the British Navy study deep-sea diving (specifically, how best to acclimate divers back to the surface without them succumbing to decompression sickness), instead of just monitoring experienced divers, Haldane recreated diving for himself in a special decompression chamber. His self-experiments ended up giving him a severe spinal cord injury, which he walked off. When asked about the intense pain that would follow him for the rest of his life, he explained simply, "I do not complain." He'd also get bloody noses as a result of the decompression and, according to legend, whenever Haldane's colleagues couldn't find him, they would simply follow the trail of blood that inevitably lead right to him.

Via Webpages.dcu.ie
"Now I'm going to need each of you to punch me in the dick until you die from exhaustion. Don't worry about me, I'll be fine."

He also suffered perforated eardrums, which he commented on like the Mark Twain of action movie stars: "The drum generally heals up; and if a hole remains in it, although one is somewhat deaf, one can blow tobacco smoke out of the ear in question, which is a social accomplishment."

Speaking of genetics, it turned out that J.B.S. Haldane's badassery ran in the family. His father, John Scott Haldane, was just as cavalier with insane self-experimentation. Haldane Sr. (1860-1936) was a Scottish physiologist who investigated the toxic effects of various poison gases. On himself. Like, sealed in a chamber. With toxic gases.

Via Newscientist.com
"Carbon dioxide? More like carbon pussyoxide. I huff a tank before breakfast."

Haldane Sr. also investigated hazards (read: death) associated with coal mining and underground sewer work. After analyzing how the toxic gaseous samples that he collected at these sites could affect (read: kill) small animals, he was the guy who suggested that underground workers start bring canaries down with them, whose deaths would warn them that a deadly gas had leaked into the work area.

One cute father-son bonding story involved Haldane Sr. taking little J.B.S. to a North Staffordshire mining pit. In order to teach him about how certain noxious gases are lighter than air, Haldane Sr. had little Jack stand upright in the pit where they were crouched down and recite Shakespeare. He did this until he passed out from the fumes.

Via CHoM News
We're pretty sure his mustache is mostly made of diamond.

Oh, you know what else? The Haldane family motto was "Suffer."

For more badass scientists, check out 5 Famous Scientists Dismissed as Morons in Their Time and 9 Inventions that Prove Leonardo da Vinci Was a Supervillain.

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