Why do you need a spy mirror (5 photos)

Surely, in films about the police, you have seen how a suspect is left alone in a room and his behavior is observed through a huge glass. A person left alone with himself does not see the police and even goes up to the mirror hanging in the room to look into it. This is called Gesell's mirror and it was not originally invented for law enforcement agencies.





Who is Gesell, after whom this mirror was named?

Arnold Louis Gesell is an American psychologist who studied the characteristics of the mental development of children from early childhood to adolescence. His research, together with other psychologists, became the beginning of the classic American trend in the development of child psychology.



Gesell at work

In 1911, Gesell opened the Yale Normal Childhood Clinic, where he studied the psyche of children from birth. He drew something like a graph: in the first three years of his life, a child experiences most of his mental development, since it is during this period that development is at its highest. Gesell's periodization reads: from birth to one year, then from one year to three years, and from three to eighteen. The first period, as is known, is the fastest in terms of the pace of mental development, the second is already average, and the third is the lowest.





In order to observe children, Gesell actively used a dome in the form of a mirror, which on the one hand was really a mirror, and on the other glass, behind which psychologists could not be seen or heard. Of course, the invention of such a mirror did not belong to a psychologist, but it was thanks to him that it became popular and began to be used not only in medicine.



Previously, in ancient times, mirrors were made like this: they covered the glass with a layer of silver (fan fact - this is precisely the reason why vampires cannot be reflected in a mirror, because silver is mortally dangerous for them).

But then, this method was replaced by a new, cheaper one. Instead of silver, they began to use aluminum and an unprofessional eye will not be able to distinguish which material was used to create the mirror.

And if you apply the thinnest titanium layer to the mirror surface, then this is where you get a Gesell mirror. On one side it is darkened but transparent, and on the other it is shiny.



Where is it used today:

for monitoring persons under investigation in police institutions;

external design of various architectural complexes;

for interior doors, sliding screens, blinds, etc. related to the interior design of different rooms;

production of glasses that are darkened on one side and transparent on the other;

car window tinting;]]

fencing at airports, train stations and other similar places;

as partitions in cafes or other public places.

Regarding the last point, it even becomes a little alarming: aren’t such mirrors used in public restrooms..?