Frank Julian Sprague was born on July 25, 1857, and died on October 25, 1934. He was an American inventor who helped develop the electric motor, electric railways, and electric elevators. His work was important for helping cities grow larger by improving transportation and allowing businesses to gather in downtown areas through the use of electric elevators in tall buildings. He was called the "father of electric traction." Sprague showed talent in science and math, and he was accepted into the U.S. Naval Academy in 1874. After graduating in 1878 and spending two years at sea, he left the Navy to work as an electrical engineer.
Early life and education
Sprague was born in Milford, Connecticut, in 1857 to David Cummings Sprague and Frances Julia King Sprague, who was a school teacher. His mother passed away when he was ten years old, and his father sent him to live with his aunt in New York. Sprague attended Drury High School in North Adams, Massachusetts, and did very well in math. After finishing high school, he traveled to Springfield, Massachusetts, to take an entrance exam for West Point. However, he unexpectedly took a four-day entrance exam for the United States Naval Academy in Annapolis, Maryland. He received the highest score (twelve other people took the exam), but needed money to attend the school. A local contractor and a bank gave him $4,000, and he traveled to Maryland. There, he graduated seventh (out of thirty-six) in the class of 1878.
Career
He was appointed as an ensign in the United States Navy. During his time in the Navy, he first worked on the USS Richmond, then the USS Minnesota. While in Asia, Sprague wrote stories for the Boston Herald. While his ship was in Newport, Rhode Island, in 1881, Sprague invented a new type of dynamo. After being transferred to the USS Lancaster, the flagship of the European Squadron, he installed the first electric call-bell system on a United States Navy ship. Sprague took time off to attend the International Exposition of Electricity in Paris in 1881 and the Crystal Palace Exhibition in Sydenham, England, in 1882, where he was part of a group that judged awards for gas engines, dynamos, and lamps.
In 1883, Edward H. Johnson, a business partner of Thomas Edison, encouraged Sprague to leave the Navy to work for Edison. Sprague started with a salary of $2,500 but was not satisfied with his pay or tasks. Sprague wanted to focus on motors, but Edison was more interested in developing his incandescent lighting system. Edison sent Sprague to manage construction departments where Edison had built power stations for his lighting systems in Sunbury, Pennsylvania, and Brockton, Massachusetts.
Sprague made important improvements to Edison’s system for distributing electricity. In 1884, he decided his interests in electricity were different from Edison’s and left to start his own company, the Sprague Electric Railway & Motor Company.
By 1886, Sprague’s company introduced two major inventions: a motor that kept a steady speed even when the load changed and a braking method that returned energy to the power system. His motor was the first of its kind and was praised by Edison as the best electric motor available. His braking system helped develop electric trains and elevators.
Sprague improved designs for electric streetcars that collected power from overhead lines. He improved a spring-loaded trolley pole created in 1885 by Charles Van Depoele, made better mounts for streetcar motors, and improved gear designs. He also showed that regenerative braking worked in practice. After testing his system in late 1887 and early 1888, Sprague built the first large electric street railway system—the Richmond Union Passenger Railway in Richmond, Virginia—which began operating on February 2, 1888. The steep hills of Richmond, with grades over 10%, proved that his technology could work in challenging areas, unlike the cable cars in San Francisco.
By the summer of 1888, Henry M. Whitney of the West End Street Railway in Boston saw multiple streetcars starting at the same time using one power source and decided to switch to electric cars. By January 1889, Boston had its first electric streetcars, which later became the first in the Americas to operate underground in the Tremont Street Subway. Poet Oliver Wendell Holmes wrote about the new trolley pole technology and the sparking contact shoe on top of it.
Within a year, electric power began replacing horse-drawn streetcars in many cities. By 1889, 110 electric railways using Sprague’s equipment were planned or started on several continents. In 1890, Edison, who made most of Sprague’s equipment, bought his company, and Sprague focused on electric elevators. However, he continued to support electric transportation and proposed expanding London’s Underground in 1901.
Sprague’s electric supply system was better than the first bipolar U-tube overhead lines, which had been used since 1883 on the Mödling and Hinterbrühl Tram.
While electrifying streetcars in Richmond, Sprague noticed that electric systems could also improve vertical transportation, like electric elevators. He believed that faster elevators could save time and increase building profits by reducing the space taken by slow hydraulic elevators.
In 1892, Sprague founded the Sprague Electric Elevator Company. With Charles R. Pratt, he developed the Sprague-Pratt Electric Elevator, the first of which was installed in the Postal Telegraph Building in 1894. The company created floor control, automatic elevators, safety systems for elevator cars, and freight elevators. These elevators were faster and could carry more weight than older hydraulic or steam elevators. By 1895, 584 elevators had been installed worldwide, and Sprague sold his company to the Otis Elevator Company.
Sprague’s work with elevators led him to create a multiple-unit system for electric trains, which helped develop electric train technology. In this system, each train car has its own electric motor. The engineer controls all the motors using wires connected to relays. For lighter trains, no locomotives are needed, so every car can generate revenue. When locomotives are used, one person can control all of them.
Sprague’s first multiple-unit order came from the South Side Elevated Railroad (part of the "L" system) in Chicago, Illinois. This success led to major contracts in Brooklyn, New York, and Boston, Massachusetts.
From 1896 to 1900, Sprague worked on the Commission for Terminal Electrification of the New York Central Railroad, including Grand Central Station in New York City. He designed an automatic train control system to follow track signals. He founded the Sprague Safety Control & Signal Corporation to build this system. With William J. Wilgus, he created the Wilgus-Sprague bottom contact third rail system used by railroads leading to Grand Central Terminal.
During World War I, Sprague worked on the Naval Consulting Board. In the 1920s, he developed a method to safely operate two separate elevators—local and express—in one shaft to save space. He sold this system, along with elevator safety systems that activated when speed or acceleration was too high, to the Westinghouse Company.
Legacy
Sprague’s improvements in electric traction allowed cities to expand, and his invention of the elevator made it possible to build more commercial structures in city centers, increasing the value of these buildings. Sprague’s work made modern light rail and subway systems possible, and these systems still operate using the same basic ideas today.
The famous Sprague-Thomson train cars used in the Paris Métro from 1908 to 1983 are still called les rames Sprague ("Sprague trainsets") today.
Sprague’s engines were used as far away as Sydney Harbour in Australia. A five-horsepower Lundell electric motor used at the Cockatoo Island Dockyard from 1900 to 1980 is now displayed at the National Museum of Australia in Canberra.
Awards and recognition
Sprague received the gold medal in Paris at the International Electricity Exposition in 1889. He also won the grand prize at the Louisiana Purchase Exposition in 1904, the Elliott Cresson Medal in 1904, and the Edison Medal from the American Institute of Electrical Engineers (now known as the Institute of Electrical and Electronics Engineers) in 1910 for "outstanding work in electrical science, engineering, and arts as shown in his contributions."
In addition, he was given the Franklin Medal in 1921 and was awarded the John Fritz Gold Medal after his death in 1935.
Personal life
Frank Sprague was married twice. His first wife was Mary Keatinge, and his second wife was Harriet Chapman Jones. Frank and Mary had one son named Frank Desmond. Frank and Harriet had two sons and one daughter: Robert C. Sprague, Julian K., and Frances A. Robert C. Sprague was also an inventor.
Frank Sprague died on October 25, 1934. He was buried with full honors from the U.S. Navy at Arlington National Cemetery in Virginia. His wife, Harriet, was buried next to him after she died in 1969. After Frank’s death, Harriet gave a large collection of materials from his personal items to the New York Public Library. These materials are still available to the public through the library’s rare books division. Other papers, including six books of letters and photographs given to Frank for his 75th birthday, are kept at the Chapin Library at Williams College.
In 1959, Harriet donated money to build the Sprague Building at the Shore Line Trolley Museum in East Haven, Connecticut. This museum is near the home where Frank grew up in Milford. It is the oldest trolley museum in the United States and has one of the largest collections of trolley items in the country.
Frank’s son, Robert C. Sprague, later became the president of Sprague Electric Company from 1926 to 1953 and its CEO from 1953 to 1987. At its peak, Sprague Electric employed 12,000 people worldwide. The company had factories in Scotland, France, Italy, Japan, and several places in the United States. It became a major maker of capacitors and other electronic parts. In 1979, Sprague Electric was bought by General Cable, and in 1992, it was acquired by Vishay Intertechnology.
Frank and Harriet’s grandson, Peter Sprague, was an entrepreneur. He became the CEO of National Semiconductor from 1965 to 1995.
Tributes
In 1999, John L. Sprague and Peter Sprague turned on a motor from 1884 at the Shore Line Trolley Museum. This museum has a permanent exhibit called "Frank J. Sprague: Inventor, Scientist, Engineer," which explains Frank J. Sprague's role as the "father of electric traction" and how electricity helped cities grow.
In 2012, the Pennsylvania Trolley Museum took in a stray cat and named it Frank the Trolley Cat after Frank J. Sprague.
In popular culture
In 2017, Sprague was featured in an episode of season 29 of American Experience, a documentary series shown on PBS. The episode, titled The Race Underground, partly told the story of the beginning of the Boston-area MBTA's streetcar network. It called Sprague "The Forgotten Hero of the American Subway."