Bell Telephone – 1876

Acoustics, variable resistance and allegations of foul play contribute to the exciting story of the invention of the telephone.

Bell TelephoneBy the latter half of the nineteenth century, telegraph lines stretched from coast to coast in the United States and had begun popping up around the world. The revolutionary invention allowed individuals to send and receive coded messages electrically over great distances, but it could not transmit sound, let alone the complex pitches and patterns of human speech.

In the early 1860s, a German teacher named Johann Phillip Reiss made the first notable inroads toward this goal, creating a primitive device for sending and receiving sound from a distance based on the makeup of the human ear. Reiss’ invention was able to transmit, if only poorly, some sounds, including bits of music. Yet it could not transmit the human voice.

Fast forward some 15 years. Alexander Graham Bell, a native of Scotland living in Boston, Massachusetts, was just one of many engineers and inventors working toward the potentially lucrative goal of improving the popular telegraph. What he ended up achieving forever set him apart from his peers. In 1876, he invented an operational telephone, one that worked well enough that his assistant could hear him proclaim, “Mr. Watson, come here, I want to see you,” from their laboratory while he was in the next room – or so the story usually goes. Skeptics have widely questioned this popular version of the telephone’s history, which also often includes a chance spill of acid onto Bell’s worktable, which supposedly activated their previously non-working communicating device. But we are getting ahead of ourselves here, and should first say a little something about the man before jumping into the myth and controversy surrounding him.

By profession, Bell was a teacher for the deaf, a line of work that ran in his family. His father, Melville Bell, invented visible speech, a symbolic system that helped the deaf communicate. Bell’s grandfather specialized in teaching speech as well, although not specifically to the deaf. From his family and his education, Bell received a thorough understanding of acoustics. This foundation helped him shape an idea of how to improve the telegraph by allowing many messages to travel across one wire at the same time. His plan was to build a harmonic telegraph that sent multiple signals simultaneously by varying their pitch. The device proved much easier to conceive, however, than to build.

Bell struggled with the harmonic telegraph through much of the early 1870s. He received funding from the president of the Clarke School for the Deaf, who would one day become his father-in-law, and a prominent local businessman. But he began to envision a device of a different kind in 1874. Some time earlier, while working on a primitive teaching aid for the deaf called the phonoautograph, Bell had discovered the principle of variable resistance. Now Bell thought that by using a membrane and varying the intensity of an electric current, he could find a way to duplicate human speech. Then, he theorized, he could send the signal across a wire to a second membrane, where the original speech could be reproduced for a waiting listener.

Now Bell had two good ideas. But because he did not have a strong background in electricity, he sought the help of someone who did — Thomas Watson. With Watson at his side, work progressed more quickly. Still, Bell’s efforts were divided. On one hand, his financial backers were anxiously awaiting the completion of a harmonic telegraph. On the other, the possibility of electrical speech transmission fascinated him. Not knowing which path to take, Bell asked Joseph Henry, at that time secretary of the Smithsonian Institution, for his opinion. Henry saw great potential in Bell’s work on the telephone and urged him to pursue it further. Bell did so fervently and, although he had not yet built a working prototype, sent the plans for his “electrical speech machine” with a patent application to the U.S. Patent Office on February 14, 1876.

Only hours after the filing of Bell’s application, Elisha Gray, an expert electrician and manufacturer of telegraph equipment from Ohio, filed a Notice of Invention for his own version of the telephone. Whether or not someone tipped Bell off regarding the contents of Gray’s Notice has been heavily debated, and no one knows for sure. The fact that one of the key principles of the telephone appears in a margin of Bell’s application suggests that it might have been added at the last minute. In either event, when Bell actually did build a working telephone, it incorporated some ideas that appeared in Gray’s plan but not his own. Ultimately, the matter of who patented what first became a matter for the courts. Following an intense legal battle, Bell eventually emerged the victor.

In 1877, Bell tried to sell his invention to Western Union for $100,000, but the telegraph company turned down his offer. This rejection inspired him to form the Bell Telephone Company. Still, the telephone had a long way to go before it evolved into a practical device that ordinary people would buy, and even further before it began to resemble the small, often portable devices we depend on today. But that’s another story!

Last modified on 10 December 2014