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The Lost Patents

The United States Patent and Trademark Office was established in 1790, and since then the federal office has issued over 10 million patents for all sorts of inventions. Virtually every patent is available to the public, either on paper or microfilm, or digitized and searchable on the Internet—except the first ten thousand patents. They went up in smoke exactly 184 years ago.

At that time, the Patent Office was housed inside the Blodget Hotel Building, in Washington, along with the post office. It was the only government building that survived the burning of Washington during the War of 1812, due to the efforts of William Thornton, the Superintendent of the Patent Office, who successfully pleaded with the British troops to spare the building.

The first patent issued by the US Patent Office

The first patent issued by the US Patent Office on July 31, 1790 to Samuel Hopkins.

The story goes that after the British had captured the city of Washington and destroyed all government buildings, Thornton put himself before a loaded cannon trained at the Patent Office and exclaimed: “Are you Englishmen or only Goths and Vandals? This is the Patent Office, a depository of the ingenuity of the American nation, in which the whole civilized world is interested. Would you destroy it? If so, fire away, and let the charge pass through my body.” Fearing condemnation from future generations, the red coats turned away.

Under William Thornton’s leadership, the Patent Office underwent steady growth. It goes without saying, the country’s inventive minds played no small a part in the office's success.

In 1836, with ten thousand patents and seven thousand patent models housed inside the Patent Office, the government decided that a bigger office was needed, and authorized the construction of a new building. That same year, a disastrous fire destroyed the current building, and all the patents and models in it, with the exception of one book—Volume VI of the Repertory of Arts and Manufacturers, which an employee of the office happened to have taken home with him.

Blodget Hotel Building

The Blodget Hotel Building was the office of the US Patent Office until 1836.

The Congress immediately passed a law allowing the patents to be reissued, and an effort was made to piece together the lost files. After ten years of work, about two thousand patents were recovered, mostly from their original inventors. But finding out who the inventors were was difficult when all the records were destroyed. Often times, the record themselves were incomplete and they frequently lacked specifications and drawings.

Also, these patents were not numbered and were referred to only by the name of the inventor and the issue date. This was changed on July 13, 1836, about five months before the fire, and the current numbering system was adopted that employs sequential numbers.

To distinguish the new patents from the ones that were lost in the fire and subsequently restored, the old patents were given different numbering—an X followed by an arbitrarily assigned number in the sequence in which they were issued. Thus the very first patent, issued on July 31, 1790, to Samuel Hopkins for an improvement “in the making of Pot ash and Pearl ash by a new Apparatus and Process” became X000001.

These patents are known as X-patents.

Effort was made to keep the sequence in order, but sometimes patents were recovered out of order, and when that happened, the recovered patent was given a fractional number such as 1/2 or 1/4 or even 7/8.

us patent no.1

Patent No. 1 issued to John Ruggles for a new rail-road wheel.

Although the work was wrapped up within ten years of the fire, lost and forgotten patents continue to surface to this day. About eight hundred more have been discovered since the Patent Office threw in the towel, thanks mostly to the work of amateur investigators.

In 2004, fourteen patents turned up in the library of Dartmouth College. Ten of those belonged to Samuel Morey, a well known inventor who had built an early internal combustion engines and was a pioneer in steamships. His family had donated the patents to the library. Many lost patents have ended up in historical archives and academic institutions. Others are in private collections.

“The X-patents are out there,” Sabra Chartrand wrote in The New York Times, “ it just takes a little faith and a lot of persistence to find them.”

# The New York Times,
# Harrison Henri dos SantosNascimento et al,
# George W. Evans,
# Official Gazette of the United States Patent Office, Volume 12,
# Office of the Historian, Foreign Service Institute,

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