Amazing events that occurred only once in the history

It is worth to look more closely at our familiar world, and it turns out that there is a lot of surprising and strange in it. And there are simply unique events that, once occurred, still amaze the imagination.

Timothy Brown, cured of AIDS

American Timothy Ray Brown, also known as the "Berlin patient", is considered the first person who managed to recover from AIDS.
In 2007, Brown was transplanted blood stem cells as part of the treatment of leukemia. A healthy donor, according to doctors, had a rare genetic mutation that provided resistance to the immunodeficiency virus and was transmitted to Brown.
After 3 years, despite the fact that Brown stopped therapy against HIV, the virus was not found in his blood or in tissues taken for biopsy.

Iron Mask

The Iron Mask is a mysterious prisoner who was transferred several times to different prisons in the 17th century. He became known thanks to Voltaire and his work "The Age of Louis XIV." It covered the theory that the prisoner was the twin brother of the king and that's why he had to wear a mask. However, this mask was velvet, and the popular theory of iron arose on the basis of rumors and conjectures.
There is another version, according to which the mask was a real Peter I, and instead of him an impostor returned to Russia.

Disappearance of the Norfolk Regiment

The senior officer of the missing company, Captain Frank Reginald Beck.
In August 1915 the battalions of the Norfolk Regiment took part in the attack on the village of Anafart (Turkey). On the way the soldiers entered the "strange cloud of fog", and when it was dispersed, 267 people simply disappeared.
In 1918, after the defeat of Turkey, Britain demanded the return of the regiment, which was considered to be captured. Turkey responded that their soldiers not only did not take the Norfolk regiment, but did not even participate in the battles with it.
Eyewitness soldiers describe the cloud in which the soldiers disappeared, as "similar in shape to a loaf of bread that does not change shape, despite the wind." Witnesses described several such clouds, which were dispersed after the Norfolk regiment had fallen into them.

The epidemic of laughter in Tanganyika (present Tanzania) in 1962

This case of mass hysteria was not the only one in history, but definitely the only epidemic of laughter ever documented.
The epidemic of laughter began on January 30, 1962, when three female students of the Christian school began to laugh uncontrollably. As a result, the school had to close for a while, and the epidemic of laughter "crawled" further.
In total, more than 1,000 people were affected by this strange hysteria. Because of it it was necessary to close 14 schools, and the epidemic lasted 18 months.
Scientists suggest that hysteria was caused by strict teachers and difficult conditions of schooling, and for children the fit of laughter became a way of a kind of rebellion.

In 1969, the Niagara Falls were dried

In 1969, the governments of the United States and Canada were forced to take measures to stop the erosion caused by the waterfall.
When the increase in the outflow of water proved to be insufficiently effective, in June 1969 Niagara was let through a new artificial canal, which allowed to create a dam and to strengthen the slopes on the summit.
The main event was, of course, the withered Niagara Falls - for the time of the work the crowds of tourists poured in there, everyone wanted to see it dry-eyed.
Photo by wikimedia.org
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