3 ms·

Something like "one way mirrors" should work. They're really just glass with a partially reflective layer. When one side is brightly lit and the other side is

Something like "one way mirrors" should work. They're really just glass with a partially reflective layer. When one side is brightly lit and the other side isn't you get the desired effect.

deleted 2y ago
[deleted]
tzs 2y ago
If the internet is to be believed they did not have one way mirrors in the 17th century. They were invented in the early 1900s. However, looking at the patent for what is supposed to be the first it says that there were earlier attempts--they just sucked because making the partially reflective layer was difficult and expensive and not durable enough when used on outdoor advertising devices. Yes, you read that right. Advertising. Technology being driven by someone's desire to show ads is not new. The thing the inventor was building was a case for displaying advertising posters. The case had a glass front, and the poster was behind the glass, with powerful lights behind the poster. When the lights were off the glass would appear to people looking at the case to be a mirror. When the lights were on the poster could be seen.
- deleted 2y ago
  [deleted]
- AlotOfReading 2y ago
  Plain glass works fine for this, but they were perfectly capable of making one way mirrors at the time. The historical term is "half silvered mirror", which were used in a lot of early scientific research in optics. Frankly you could just use blinds though.
  - tzs 2y ago
    If the internet is to be believed silvered mirrors also came after the 17th century. Wikipedia has silvered mirrors as being from 1835.
    - AlotOfReading 2y ago
      Silvering is a separate and older process than silver mirrors, as in the metal silver applied to a glass surface. The Wikipedia page on silvering points to the 1400s in Europe, and the 10th century for the eastern Mediterranean : https://en.wikipedia.org/wiki/Silvering https://en.wikipedia.org/wiki/Silvering

Something like "one way mirrors" should work. They're really just glass with a partially reflective layer. When one side is brightly lit and the other side isn't you get the desired effect.

deleted 2y ago

[deleted]

tzs 2y ago

If the internet is to be believed they did not have one way mirrors in the 17th century. They were invented in the early 1900s. However, looking at the patent for what is supposed to be the first it says that there were earlier attempts--they just sucked because making the partially reflective layer was difficult and expensive and not durable enough when used on outdoor advertising devices. Yes, you read that right. Advertising. Technology being driven by someone's desire to show ads is not new. The thing the inventor was building was a case for displaying advertising posters. The case had a glass front, and the poster was behind the glass, with powerful lights behind the poster. When the lights were off the glass would appear to people looking at the case to be a mirror. When the lights were on the poster could be seen.

deleted 2y ago
[deleted]
AlotOfReading 2y ago
Plain glass works fine for this, but they were perfectly capable of making one way mirrors at the time. The historical term is "half silvered mirror", which were used in a lot of early scientific research in optics. Frankly you could just use blinds though.
- tzs 2y ago
  If the internet is to be believed silvered mirrors also came after the 17th century. Wikipedia has silvered mirrors as being from 1835.
  - AlotOfReading 2y ago
    Silvering is a separate and older process than silver mirrors, as in the metal silver applied to a glass surface. The Wikipedia page on silvering points to the 1400s in Europe, and the 10th century for the eastern Mediterranean : https://en.wikipedia.org/wiki/Silvering https://en.wikipedia.org/wiki/Silvering