This 19th-century dress held a hidden message: The meaning explained

Sara Rivers Cofield had never seen a Victorian outfit like the one she saw in the antique mall in Maine.

Its lace cuffs, fluffy bustle, and fitting bodice were reminiscent of a bygone period. It was identified as an 1880s garment by Rivers Cofield, a collector of historical costumes, yet its fine embroidery, bronze silk, and metallic buttons seemed undamaged.

She negotiated the price from $125 to $100 because she was unsure of where to keep the two-piece outfit. Being an archaeologist who enjoys collecting vintage handbags and costumes, the cost was more than she often pays. But she indulged since it was the holidays.

Ten years later, Rivers Cofield was unaware that the garment she purchased in December 2013 would turn out to be a mystery. Two crumpled sheets of paper containing lists of seemingly odd words and locations—Bismark, omit, leafage, buck, bank Calgary, Cuba, unguard, confute, duck, Fagan—were hidden inside a pocket under the hustle and bustle.

Time seemed to be represented by notes on the sheets' margins. Bennett's name was scrawled on a tag sewn onto the outfit.

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Attempts to crack the code

While visiting her mother in Searsport, Maine, Rivers Cofield, an archeological curator from Chesapeake Beach, Maryland, purchased the outfit. Following her blog article, she didn't give it much thought.

She was unaware, however, that inquisitive amateur detectives were trying to unravel the riddle. They developed conspiracy theories around the words and named it the "silk dress cryptogram." Bennett was suspected of being a spy who communicated using coded phrases.

One blogger offered further possibilities in 2017 and included the note in his list of the Top 50 unanswered encrypted texts. Was it a mysterious love letter? What are the dress measurements? Codes from the Civil War?

Any interpretation associated with the Civil War was promptly rejected by Rivers Cofield. She was certain that the garment was from the 1880s since she had researched the department store chain Bloomingdale's 1880s catalogs. About 20 years had passed since the end of the conflict.

Others hypothesized that it was a communication method similar to the telegraph, a novel method of transmitting brief messages that was introduced in the United States in the 1800s and charged senders a fee based on the word count of their messages.

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Success at cracking the code

In the summer of 2018, Wayne Chan, a scholar at the University of Manitoba in Canada, discovered the code online. None of the 170 code books he examined matched the message.

After that, Chan, who enjoys cracking codes, started studying the telegraph period, especially the meteorological codes that were in use in North America at the time. He also made a breakthrough early last year.

The hidden letters turned out to be a weather forecast, he found out. According to Chan, the reason they were encrypted was not for privacy but rather because the technique enabled forecasters to condense lengthy weather forecasts into a few words.

Such shorthand was less expensive than sending a large number of words and temperature data during the telegraph era. At a particular place and time of day, each term stood for a meteorological variable, such as temperature, wind speed, and barometric pressure.

For instance, there are unexpectedly exact details in the sentence "Bismark Omit leafage buck bank." "Bismark" denoted that it was captured at the Bismarck station in modern-day North Dakota.

"Omit" indicated that the barometric pressure was 0.08 inches of mercury and the air temperature was 56 degrees. A dew point of 32 degrees Fahrenheit recorded at 10 p.m. was referred to as "leafage."

"Bank" denoted a clear sunset and a wind speed of 12 mph, while "buck" denoted no precipitation.

According to Chan, all weather stations have to telegraph their reports to a central office located in Washington, DC.

Chan found that the signals were encoded using a telegraphic weather code from the 19th century, which was employed by the Army Signal Corps, the US national meteorological agency in the late 19th century.

He pointed out that a codeword like "crimping" may be used to simplify a sentence like "The crew are all drunk."

According to Chan, he has no idea how the terms were chosen. Meteorologists used a weather codebook to figure out what words they were unfamiliar with meant. He said that they eventually learned the codewords without having to go to the codebook.

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Pinpointing the exact day of the weather report

Chan explained the subject in an academic study. Additionally, he sent an email to Rivers Cofield, who was unaware that internet detectives were still trying to crack the codes.

Although she was taken aback by the disclosure, Rivers Cofield claimed she was not shocked.

Chan was able to pinpoint the exact date of the weather measurements in the coded note—May 27, 1888—by using historical weather maps that the National Oceanic and Atmospheric Administration supplied as part of his investigation.

One of the most important lessons learned from the find, according to Rivers Cofield, is that in the 1880s, individuals had no quick method of predicting what weather was coming.

Bennett's identity and the reason she kept weather codes in a hidden pocket remain unknown.

For the time being, however, Chan and Rivers Cofield are just relieved that they have solved the largest riddle surrounding the clothing.