Granville T. Woods

Learning Objectives

By the end of this lesson, students will be able to:

• Describe how Granville T. Woods taught himself engineering after leaving school at age ten.
• Explain what the induction telegraph did — and why trains that could talk to stations mattered.
• Explain what a patent interference is — and how Woods proved he was the first to invent the induction telegraph.
• Describe Woods’s work on electric railways in New York — and the companies that bought his patents.
• Explain how Woods came to lie in an unmarked grave — and how he was finally honored.
• Evaluate why an inventor with more than fifty patents was left out of the history most students are taught.

Key Vocabulary

• Patent — A legal right from the government that says an invention belongs to the person who created it. For a set number of years, no one else can make or sell it without permission. [1]Woods, Granville T. “Induction Telegraph System.” U.S. Patent No. 373,915, November 29, 1887. United States Patent and Trademark Office. The induction telegraph.
• Patent interference — A hearing held by the United States Patent Office when two or more inventors claim the same invention. The inventor who proves he conceived it first wins the patent. [4]“The Black Edison: Granville T. Woods.” IPWatchdog, February 3, 2014. The Phelps and Edison interferences and the job-offer story.
• Induction — A way to send an electric signal across a gap with no wires touching. A changing current in one coil creates a current in a coil nearby. [3]“November 29, 1887: Granville Woods Patents the Induction Telegraph.” APS News, American Physical Society, October 2023. His birth, smallpox, the induction telegraph, and the 1975 headstone.
• Induction telegraph — Woods’s 1887 invention. It let moving trains send and receive messages to and from stations and other trains. [1]Woods, Granville T. “Induction Telegraph System.” U.S. Patent No. 373,915, November 29, 1887. United States Patent and Trademark Office. The induction telegraph.[3]“November 29, 1887: Granville Woods Patents the Induction Telegraph.” APS News, American Physical Society, October 2023. His birth, smallpox, the induction telegraph, and the 1975 headstone.
• Telegraphony — Woods’s 1885 invention that could send both voice and telegraph messages over a single wire. The American Bell Telephone Company bought the rights. [2]Fouché, Rayvon. Black Inventors in the Age of Segregation: Granville T. Woods, Lewis H. Latimer, and Shelby J. Davidson. Baltimore: Johns Hopkins University Press, 2003. Woods’s life, work, patents, and patent disputes.[10]“Granville T. Woods Way Debuts in Coney.” Brooklyn Paper, 2008. The street co-naming, P.S. 335, and the companies that bought his inventions.
• Overhead conducting system — Woods’s 1888 patent for overhead electric lines that powered streetcars and electric trains. [2]Fouché, Rayvon. Black Inventors in the Age of Segregation: Granville T. Woods, Lewis H. Latimer, and Shelby J. Davidson. Baltimore: Johns Hopkins University Press, 2003. Woods’s life, work, patents, and patent disputes.
• Self-taught — Learning a subject on your own through reading and hands-on work instead of formal school. [2]Fouché, Rayvon. Black Inventors in the Age of Segregation: Granville T. Woods, Lewis H. Latimer, and Shelby J. Davidson. Baltimore: Johns Hopkins University Press, 2003. Woods’s life, work, patents, and patent disputes.

The Full Lesson

Part 1 — From Columbus to the Railroad

Granville T. Woods was born in Columbus, Ohio, on April 23, 1856. His family was poor. He left school at about age ten and went to work. He kept learning anyway. He studied on his own and learned by doing. [2]Fouché, Rayvon. Black Inventors in the Age of Segregation: Granville T. Woods, Lewis H. Latimer, and Shelby J. Davidson. Baltimore: Johns Hopkins University Press, 2003. Woods’s life, work, patents, and patent disputes.[3]“November 29, 1887: Granville Woods Patents the Induction Telegraph.” APS News, American Physical Society, October 2023. His birth, smallpox, the induction telegraph, and the 1975 headstone.

In 1872, he worked as a fireman on a railroad in Missouri — feeding the engine and learning how it ran. He also worked in a rolling mill and in a machine shop. In 1878, he took a job aboard a steamship called the Ironsides. Within two years, he became its chief engineer. Every job taught him more about engines and electricity. [2]Fouché, Rayvon. Black Inventors in the Age of Segregation: Granville T. Woods, Lewis H. Latimer, and Shelby J. Davidson. Baltimore: Johns Hopkins University Press, 2003. Woods’s life, work, patents, and patent disputes.

"Every job taught him more about engines and electricity."

Part 2 — The Inventor in Cincinnati

Around 1880, Woods settled in Cincinnati, Ohio. There he opened his own company to build and sell electrical equipment. Then, in 1881, he caught smallpox. For months he was too sick to work. His health was never the same. He kept inventing. [2]Fouché, Rayvon. Black Inventors in the Age of Segregation: Granville T. Woods, Lewis H. Latimer, and Shelby J. Davidson. Baltimore: Johns Hopkins University Press, 2003. Woods’s life, work, patents, and patent disputes.[3]“November 29, 1887: Granville Woods Patents the Induction Telegraph.” APS News, American Physical Society, October 2023. His birth, smallpox, the induction telegraph, and the 1975 headstone.

In 1884, he received his first patent. It was for an improved steam boiler furnace. In 1885, he patented telegraphony — a system that could send voice and telegraph messages over the same wire. The American Bell Telephone Company bought the rights. In 1886, a Cincinnati newspaper called him the greatest electrician in the world. [2]Fouché, Rayvon. Black Inventors in the Age of Segregation: Granville T. Woods, Lewis H. Latimer, and Shelby J. Davidson. Baltimore: Johns Hopkins University Press, 2003. Woods’s life, work, patents, and patent disputes.[5]Walnut Hills Historical Society. “Granville T. Woods, Electrical Engineer.” Walnut Hills Stories. 1880s Cincinnati newspaper reports and the sale of the patent to the Edison interests.[10]“Granville T. Woods Way Debuts in Coney.” Brooklyn Paper, 2008. The street co-naming, P.S. 335, and the companies that bought his inventions.

"In 1886, a Cincinnati newspaper called him the greatest electrician in the world."

Part 3 — Trains That Could Talk

In the 1880s, a moving train was cut off from the world. Once it left the station, no one could reach it — and it could not reach anyone else. Woods set out to change that. His answer was the induction telegraph. [3]“November 29, 1887: Granville Woods Patents the Induction Telegraph.” APS News, American Physical Society, October 2023. His birth, smallpox, the induction telegraph, and the 1975 headstone.

A coil of wire on the train passed close to a telegraph wire running beside the track. Signals jumped the gap through induction. No wires had to touch. With it, moving trains could send and receive messages to and from stations and other trains. The patent was granted on November 29, 1887. [1]Woods, Granville T. “Induction Telegraph System.” U.S. Patent No. 373,915, November 29, 1887. United States Patent and Trademark Office. The induction telegraph.[3]“November 29, 1887: Granville Woods Patents the Induction Telegraph.” APS News, American Physical Society, October 2023. His birth, smallpox, the induction telegraph, and the 1975 headstone.

"Signals jumped the gap through induction. No wires had to touch."

Part 4 — Defending What Was His

Woods filed for his induction telegraph patent in 1885. Another inventor, named Lucius Phelps, claimed the same idea. The Patent Office held an interference to decide who came first. Woods used his notes, his sketches, and a working model. He proved the idea was his. In 1887, Woods won. [4]“The Black Edison: Granville T. Woods.” IPWatchdog, February 3, 2014. The Phelps and Edison interferences and the job-offer story.

Then Thomas Edison challenged the patent. He claimed that he was the first inventor. The Patent Office ruled for Woods. Edison challenged again. Woods won again. [4]“The Black Edison: Granville T. Woods.” IPWatchdog, February 3, 2014. The Phelps and Edison interferences and the job-offer story.[5]Walnut Hills Historical Society. “Granville T. Woods, Electrical Engineer.” Walnut Hills Stories. 1880s Cincinnati newspaper reports and the sale of the patent to the Edison interests.[6]“Granville T. Woods: The Cincinnati Inventor Who Beat Thomas Edison.” Cincinnati Magazine. Edison’s two challenges to the induction telegraph patent.

A story is often told that Edison then offered Woods a job — and that Woods said no. Some writers on patent history say that story may be folklore. What the record does show is that the long fight ended with Woods selling the patent to Edison’s business interests for a relatively small sum. [4]“The Black Edison: Granville T. Woods.” IPWatchdog, February 3, 2014. The Phelps and Edison interferences and the job-offer story.[5]Walnut Hills Historical Society. “Granville T. Woods, Electrical Engineer.” Walnut Hills Stories. 1880s Cincinnati newspaper reports and the sale of the patent to the Edison interests.

"The Patent Office ruled for Woods. Edison challenged again. Woods won again."

Part 5 — Powering the Cities

In 1888, Woods patented an overhead conducting system — overhead electric lines that powered streetcars and electric trains. In the 1890s, he moved to New York City. [2]Fouché, Rayvon. Black Inventors in the Age of Segregation: Granville T. Woods, Lewis H. Latimer, and Shelby J. Davidson. Baltimore: Johns Hopkins University Press, 2003. Woods’s life, work, patents, and patent disputes.

He kept inventing for the railways. He patented ways to bring electric power to moving trains, and improved air brakes to help trains stop safely. He sold patents to companies including General Electric and Westinghouse. By the end of his life, he held more than fifty patents. [2]Fouché, Rayvon. Black Inventors in the Age of Segregation: Granville T. Woods, Lewis H. Latimer, and Shelby J. Davidson. Baltimore: Johns Hopkins University Press, 2003. Woods’s life, work, patents, and patent disputes.[9]National Inventors Hall of Fame. “Granville T. Woods.” Inducted 2006.[10]“Granville T. Woods Way Debuts in Coney.” Brooklyn Paper, 2008. The street co-naming, P.S. 335, and the companies that bought his inventions.

"By the end of his life, he held more than fifty patents."

Part 6 — Forgotten and Remembered

Granville T. Woods died in New York City on January 30, 1910. He had little money. He was buried in an unmarked grave in Saint Michael’s Cemetery in Queens, in a coffin he shared with two infants and another adult. For sixty-five years, nothing marked the spot. [2]Fouché, Rayvon. Black Inventors in the Age of Segregation: Granville T. Woods, Lewis H. Latimer, and Shelby J. Davidson. Baltimore: Johns Hopkins University Press, 2003. Woods’s life, work, patents, and patent disputes.[3]“November 29, 1887: Granville Woods Patents the Induction Telegraph.” APS News, American Physical Society, October 2023. His birth, smallpox, the induction telegraph, and the 1975 headstone.[7]The New York Review of Books. Essay on St. Michael’s Cemetery, East Elmhurst, Queens, 2026. The unmarked grave, the shared coffin, and Middleton Harris’s markers.

Then, in 1975, a historian named Middleton Harris raised money for a marker. Companies that had used Woods’s inventions helped pay for it. In 2006, Woods was inducted into the National Inventors Hall of Fame. A school in Brooklyn now carries his name. So does a street at Coney Island: Granville T. Woods Way. [3]“November 29, 1887: Granville Woods Patents the Induction Telegraph.” APS News, American Physical Society, October 2023. His birth, smallpox, the induction telegraph, and the 1975 headstone.[7]The New York Review of Books. Essay on St. Michael’s Cemetery, East Elmhurst, Queens, 2026. The unmarked grave, the shared coffin, and Middleton Harris’s markers.[8]New York State Assembly. Resolution No. 783, 2021. The 1975 marker at St. Michael’s Cemetery and P.S. 335, the Granville T. Woods School.[9]National Inventors Hall of Fame. “Granville T. Woods.” Inducted 2006.[10]“Granville T. Woods Way Debuts in Coney.” Brooklyn Paper, 2008. The street co-naming, P.S. 335, and the companies that bought his inventions.

He taught himself. He beat the most famous inventor in America at the Patent Office. Twice. [4]“The Black Edison: Granville T. Woods.” IPWatchdog, February 3, 2014. The Phelps and Edison interferences and the job-offer story.[6]“Granville T. Woods: The Cincinnati Inventor Who Beat Thomas Edison.” Cincinnati Magazine. Edison’s two challenges to the induction telegraph patent.

"History almost let the world forget him."

Critical Thinking Discussion Questions

1. Woods left school at about age ten but became one of the leading electrical inventors of his time. [2]Fouché, Rayvon. Black Inventors in the Age of Segregation: Granville T. Woods, Lewis H. Latimer, and Shelby J. Davidson. Baltimore: Johns Hopkins University Press, 2003. Woods’s life, work, patents, and patent disputes. What does his path tell us about the difference between schooling and learning?
2. Before the induction telegraph, a moving train could not reach anyone. [3]“November 29, 1887: Granville Woods Patents the Induction Telegraph.” APS News, American Physical Society, October 2023. His birth, smallpox, the induction telegraph, and the 1975 headstone. What dangers and problems might that have caused, and how would communication change that?
3. Woods proved he was the first inventor by using his notes, his sketches, and a working model. [4]“The Black Edison: Granville T. Woods.” IPWatchdog, February 3, 2014. The Phelps and Edison interferences and the job-offer story. Why does careful record keeping matter so much for inventors?
4. Woods won at the Patent Office but still sold the patent for a small sum. [5]Walnut Hills Historical Society. “Granville T. Woods, Electrical Engineer.” Walnut Hills Stories. 1880s Cincinnati newspaper reports and the sale of the patent to the Edison interests. Why might winning a legal fight not be enough to make an inventor wealthy?
5. Woods held more than fifty patents yet was buried in an unmarked grave. [7]The New York Review of Books. Essay on St. Michael’s Cemetery, East Elmhurst, Queens, 2026. The unmarked grave, the shared coffin, and Middleton Harris’s markers.[9]National Inventors Hall of Fame. “Granville T. Woods.” Inducted 2006. What does his story suggest about who gets remembered in history, and why?

Quiz — Granville T. Woods

Part A: Select the best answer and check your work instantly. Part B: Write in complete sentences.

Part A — Multiple Choice

Part B — Short Answer

Extension Activity

Read the Patent: Find Woods’s induction telegraph patent — United States Patent No. 373,915, granted November 29, 1887. It is free to read online through Google Patents. Then describe three things: (1) what problem Woods says his invention solves, (2) how the drawings show the coil on the train and the wire beside the track, and (3) one word or phrase in the patent that you had to look up. Then write two to three sentences explaining why patent records are strong evidence of who invented what.