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Unit 731 -

Unit 731 was a notorious branch of the Japanese Imperial Army that engaged in lethal experiments on Chinese civilians during the Second Sino-Japanese War and World War II.

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Unit 731 -

Established in the 1930s, the sinister facility, headed by General Shirō Ishii (pictured), killed an estimated 30,000 people as Japan sought to develop biological weapons.

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Unit 731 -

Japan only acknowledged the existence of Unit 731 in the late 1990s, its activities constituting some of the gravest war crimes committed by the country's armed forces between 1937 and 1945. Today, a museum inside the remnants of Unit 731 exists to remind the world of the dreadful loss of life that took place within its walls.

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Tuskegee Syphilis Study -

The Tuskegee Syphilis Study was one of the most controversial experiments ever conducted on American soil, a secretive 40-year program conducted on a group of African-American men with syphilis that was only exposed in 1972.

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Tuskegee Syphilis Study -

In 1932, the United States Public Health Service (PHS), together with the Tuskegee Institute, began a study to record the evolution of the sexually transmitted infection when left untreated. Participants were told they were being treated for "bad blood."

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Tuskegee Syphilis Study -

As an incentive for participation in the study, the men were promised free medical care. Over the course of research, however, 28 died as a direct result of the disease, with another 100 succumbing from complications. In 1994, President Bill Clinton apologized to the survivors and families of the victims of the Tuskegee Syphilis Study. Among those present at the White House ceremony was 94-year-old Herman Shaw (pictured), one of the few who withstood the terrible ordeal.

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Dolly the sheep -

On July 5, 1996, the first mammal to be cloned from an adult cell was born—Dolly the sheep.

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Dolly the sheep -

Dolly, a female domestic sheep, was genetically copied by Keith Campbell, Ian Wilmut (pictured), and colleagues at the Roslin Institute, part of the University of Edinburgh, Scotland.

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Dolly the sheep -

The scientific breakthrough was announced to the world in February 1997. Dolly's existence was made possible by a process called nuclear transfer. The animal lived for six years, and produced six lambs. She was euthanized in 2003 after developing a progressive lung disease and severe arthritis. No cause which linked the disease to her cloning was found.

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The Emma Eckstein case -

One of the most bizarre cases of medical malpractice took place over a hundred years ago and involved two of the most eminent names of the era—Austrian psychoanalyst Sigmund Freud (pictured) and German otolaryngologist Wilhelm Fliess.

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The Emma Eckstein case -

Their patient was Emma Eckstein, whom Freud had referred to Fliess for surgery to remove the turbinate bone from her nose, ostensibly to cure her of premenstrual depression.

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The Emma Eckstein case -

Fliess believed that sexual problems were linked to the nose, a condition he called "nasal reflex neurosis." The subsequent procedure proved disastrous, with Eckstein bleeding profusely and left permanently disfigured.

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Henry Cotton's experimental surgery -

American psychiatrist Dr. Henry Cotton is infamous for a series of horrific experiments conducted in the name of medical science on patients at the New Jersey State Hospital at Trenton during the early 20th century.

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Henry Cotton's experimental surgery -

During his tenure from 1907 to 1930, Cotton and his staff employed numerous experimental surgery and bacteriology techniques on dozens of mentally ill residents in an effort to "save" them.

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Henry Cotton's experimental surgery -

Cotton's slipshod methods included the removal of infected teeth in the belief that doing so would cure the mentally ill. But his warped insanity theory led to hundreds of fatalities and thousands of maimed and mutilated patients.

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Project MKUltra -

In 1953, the CIA embarked on an illegal human experimentation program it hoped would allow control of the thought process. Codenamed Project MKUltra, it was headed by CIA chemist Sidney Gottlieb. Pictured is a declassified but heavily redacted letter signed by Gottlieb approving the use of LSD in the interrogation of enemies of the state.

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Project MKUltra -

Hallucinogens like LSD proved useful in the CIA's quest to develop a mind control drug that could be weaponized against enemies. Under MKUltra, often-unwilling subjects were also put through sleep and sensory deprivation, hypnosis, isolation, verbal and sexual abuse, and other kinds of psychological torture.

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Project MKUltra -

In addition, electroshock treatment was administered on a regular basis. Some of these tests proved lethal. MKUltra was halted in 1972 and revealed to the public in 1975, though most of the incriminating documentation had been destroyed two years earlier.

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Nazi concentration camp experiments -

The experiments carried out by the Nazis during the Second World War, ostensibly to further medical science, rank among the most diabolical and inhumane in recorded history. Dr. Josef Mengele (pictured center) was responsible for carrying out the heinous crimes.

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Nazi concentration camp experiments -

Mengele, the SS physician dubbed the "Angel of Death" by inmates, oversaw and directly took part in the unnecessary amputation of limbs, the injection of chloroform into healthy hearts, and deliberately infecting subjects with deadly bacteria, among other atrocities.

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Nazi concentration camp experiments -

In February 1979, aged 67, Mengele died having escaped justice. Historians estimate that around 1.1 million people perished in Auschwitz-Birkenau during the less than five years of its existence.

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The language deprivation experiment -

Also referred to as the Roman emperor baby experiment, this cruel and unorthodox study was carried out by Holy Roman Emperor Frederick II, in the early 13th century.

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The language deprivation experiment -

Frederick II had an interest in the origins of language. To that end, he ordered that five young infants be raised without human interaction in an attempt to determine if there was a natural language that they might demonstrate once their voices matured.

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The language deprivation experiment -

No interaction meant no touching, no talking, and no outward display emotion. The youngsters were being raised in a completely mute world. The results were disastrous. After three years of language deprivation, the emotionally-starved quintet was dead.

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Large Hadron Collider -

Between 1998 and 2008, science fiction slowly became science fact with the development of the Large Hadron Collider (LHC), the world's largest and highest-energy particle collider.

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Large Hadron Collider -

Designed and built by the Geneva-based European Organization for Nuclear Research (CERN), LHC lies in a tunnel 27 km (17 mi) in circumference and as deep as 175 m (574 ft) beneath the France–Switzerland border.

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Large Hadron Collider -

While the LHC particle collisions pose no conceivable threat ("it's absolutely safe," assures CERN), the LHC has been blamed by some for causing earthquakes, pulling asteroids towards Earth, and even creating black holes.

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Project Mohole -

Project Mohole is a little-known experiment conducted in the 1960s, the aim of which was to drill through the Earth's crust to obtain samples of the Mohorovičić discontinuity, or Moho. A huge oil drill ship, CUSS 1 (pictured), was deployed to carry out the ambitious project.

Image: US Government. 

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Project Mohole -

Moho is the boundary between the Earth's crust and mantle. Project Mohole, funded by the National Science Foundation, was intended to provide an earth science complement to the high-profile Space Race that scientists believed would provide invaluable information on the Earth's age, makeup, and internal processes.

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Project Mohole -

The drill ship was steadied by submerged buoys (pictured) used for dynamic positioning. Accusations of mismanagement and spiraling costs, however, meant that in 1966 Congress pulled the plug on Mohole and the project sunk.

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The Trinity Test -

The world's most consequential scientific experiment took place on July 16, 1945. Known as the Trinity Test, it constituted the first ever detonation of a nuclear device.

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The Trinity Test -

The test was of an implosion-design plutonium bomb, nicknamed the "gadget." Twelve days later, on August 6, 1945, the world's first atomic bomb was detonated over Hiroshima. On August 9, a similar device exploded over Nagasaki.

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The Trinity Test -

Trinity ushered in the atomic age and the subsequent Cold War. Pictured are the scorch marks of the blast wave on the desert floor around the test site in New Mexico.

Sources: (The Guardian) (CDC) (University of Edinburgh) (Oxford Academic) (NPR) (Signs of the Times) (Daily Express)

See also: The dawn of the nuclear age: Los Alamos and beyond

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