World’s mysterious cipher decoded after 130 years: What it was hiding
A routine weather report became a global mystery (photo: Unsplash)
The puzzle known as the Silk Dress Cryptogram has finally been solved. Scientists managed to decode notes found in 2013 inside a hidden pocket of a woman’s dress from the 1880s, purchased at an antique shop in the state of Maine, according to Popular Mechanics.
When researcher Sarah Rivers-Cofield found crumpled papers with strings of words like “Bismark omit leafage buck bank” inside the dress, she published them online, hoping for help from enthusiasts.
For more than a decade, the cipher ranked among the world’s top 50 most mysterious unsolved codes. Numerous theories emerged, ranging from gambling codes and tailoring measurements to secret espionage reports.
The breakthrough came when data analyst Wayne Chan from the University of Manitoba examined old military telegraph codebooks. He discovered that the phrases in the dress were encoded weather observations sent to the U.S. Army Signal Corps office (a predecessor of the National Weather Service) in the late 1880s.
How did the 19th-century code work?
The system, adopted in 1887, was designed to reduce telegraph costs, where payment was charged per word.
Each word in the dress corresponded to a specific weather parameter:
- location (for example, Bismarck, Dakota Territory)
- temperature and barometric pressure
- dew point
- precipitation, wind direction, and wind speed
- cloud cover
Thus, the phrase “Bismarck, omit, leafage, buck, bank” indicated that in Bismarck, the temperature was 56°F, barometric pressure was 30.08 inches of mercury, dew point was 32°F, the sky was clear, winds were from the north, and wind speed was 12 mph.
Who left the papers?
Although the code has been deciphered (likely dating back to May 27, 1888), the main mystery remains unsolved: who owned the dress and why the notes were hidden in a secret pocket.
The name “Bennett” appears on the dress lining, but attempts to link it to women working in meteorological services of the time have not led to conclusive results.
Researchers suggest the dress may have belonged to a telegraph operator or someone involved in data transmission systems, but over 130 years, its history could have changed multiple times through resale or gifting.
While the cipher itself is no longer a mystery, the identity of the dress’s owner remains just as puzzling as before.
