Two filings, one day
The most famous coincidence in the history of the telephone took place at the United States Patent Office on February 14, 1876. On that date, a patent application from Alexander Graham Bell, prepared with the help of his lawyers, was filed. On the same date, the electrical inventor Elisha Gray filed a caveat, a preliminary notice that stated that he was working on a similar device and intended to patent it. Both documents dealt with transmitting speech by electric current.
That much is agreed. What is much less agreed is the order in which the two papers arrived, and whether anyone at the Patent Office or elsewhere let one inventor see the other’s work.
What is well documented
Several facts are solid.
- Bell’s application was filed on February 14, 1876, and the patent was granted on March 7, 1876. It is a famous patent, and it covered a method of transmitting sounds by undulating electric current.
- Gray’s caveat was filed the same day. A caveat was not a patent. It gave an inventor a period of protection while he completed his invention, and it would have triggered a review if another application on the same subject appeared.
- Bell was a teacher of the deaf with a background in the physics of speech. Gray was an experienced electrical manufacturer who was a founder of what became Western Electric.
- Both men had been working on telegraph systems that used different tones, the so-called harmonic telegraph, and both were moving toward the same insight about speech.
- The Patent Office granted Bell’s patent, and in the years following, courts upheld it.
What is disputed
Beyond those facts, accounts diverge.
Order of filing. Some accounts say Bell’s application was entered before Gray’s caveat, others say Gray’s came first, and some stress that the exact order of two papers on one day is hard to establish. An older tradition holds that Bell’s lawyer filed early in the day, while Gray’s papers arrived later in the day. The record is open to different readings.
The liquid transmitter. Gray’s caveat described a transmitter in which a diaphragm moved a needle in a liquid, changing the resistance of the circuit. Bell’s notebook entry from March 1876, shortly after his patent was granted, sketches a transmitter that works in a similar way, and his assistant’s account of the first sentence involved a liquid transmitter. Some historians argue that this resemblance points to improper knowledge of Gray’s design, and others point out that Bell’s patent already mentioned the variable resistance principle and that the idea was part of the ongoing work of the time.
Allegations of improper influence. In later years, a patent examiner named Zenas Wilber stated in an affidavit that he had shown Bell details of Gray’s caveat. His statements were used in efforts to challenge Bell’s patents. They were disputed, and the reliability of his account has itself been questioned. Authors who have studied the subject in depth reach different conclusions, and it is reasonable to say that the question has not been settled beyond doubt.
Other claimants
The story is complicated further by several other inventors.
- Antonio Meucci had filed a caveat in 1871 on a voice-transmission device and renewed it until 1874, but he never obtained a patent. The United States House of Representatives passed a resolution in 2002 recognizing his contributions, while historians continue to discuss what his device could actually do.
- Philipp Reis built a device in the early 1860s that could transmit musical tones, and perhaps some speech, but the quality was poor.
- Daniel Drawbaugh, a Pennsylvania mechanic, claimed to have made a working telephone before Bell. His case went as far as the Supreme Court, which did not accept his claim as proven.
- Amos Dolbear and others also claimed priority at various points.
The lawsuits
Bell’s company defended its patents in many lawsuits during the 1880s. The most important cases were heard together by the United States Supreme Court, and in 1888 the Court upheld Bell’s patents in a divided decision. A separate action brought by the government in 1887 to cancel Bell’s patent dragged on for years and ended without achieving that result. By then the patents had expired or were about to, since they ran for seventeen years from 1876.
The legal outcome matters. A patent system decides who has the right to exclude others, not who had the idea first. That is why a court can uphold a patent while historians still debate the invention.
Similar stories
Disputes over priority were not unusual in that period. The telegraph and many other devices had overlapping claimants, from the long list of bulb inventors working on incandescent bulbs to the rivals in wireless telegraphy and, later, electronic television. Simultaneous invention happens often when the knowledge needed is available to many people at once, and a patent system that rewards the first to file can give outsized credit to one person. Patent battles also shaped other fields, from the Wright brothers’ lawsuits in early aviation to modern technology.
A reasonable summary
It is accurate to say that Bell received the first patent that covered the telephone, that Gray filed a related caveat on the same day, and that other people worked on voice transmission earlier or at the same time. It is not accurate to say that either man alone created the telephone from nothing, or to state as proven that Bell copied Gray. A careful account says what the documents show, notes what the later testimony claims, and leaves the rest as open.