Frank Julian Sprague (July 25, 1857 in
Milford, ConnecticutMilford is a city in southwestern New Haven County, Connecticut, United States, located between Bridgeport and New Haven. The population was 50,594 at the 2000 census. The city contains the incorporated borough of Woodmont and the unincorporated village of Devon. The current mayor of Milford is...
- October 25, 1934) was an
AmericanThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
naval officerA navy is the branch of a nation's armed forces principally designated for naval warfare and amphibious warfare; namely, lake- or ocean-borne combat operations and related functions...
and
inventorAn inventor is a person who creates or discovers a new method, form, device or other useful means. The word inventor comes form the latin verb invenire, invent-, to find...
who contributed to the development of the
electric motorAn electric motor uses electrical energy to produce mechanical energy, usually through the interaction of magnetic fields and current-carrying conductors. The reverse process, producing electrical energy from mechanical energy, is accomplished by a generator or dynamo. Traction motors used on...
,
electric railwaysA railway electrification system supplies electrical energy to railway locomotives and multiple units so that they can operate without having an on-board prime mover. There are several different electrification systems in use throughout the world...
, and
electric elevatorsAn elevator or lift is a vertical transport vehicle that efficiently moves people or goods between floors of a building...
. His contributions were especially important in promoting
urbanUrbanization is the physical growth of urban areas from rural areas as a result of population immigration to an existing urban area. Effects include change in density and administration services. While the exact definition and population size of urbanized areas varies amongdifferent countries,...
development by increasing the size cities could reasonably attain (through better transportation) and by allowing greater concentration of business in commercial sections (through use of electric elevators in
skyscraperA skyscraper is a tall, continuously habitable building. There is no official definition or height above which a building may clearly be classified as a skyscraper...
s). He became known as the "Father of Electric Traction".
Childhood, education
Sprague was born in
Milford, ConnecticutMilford is a city in southwestern New Haven County, Connecticut, United States, located between Bridgeport and New Haven. The population was 50,594 at the 2000 census. The city contains the incorporated borough of Woodmont and the unincorporated village of Devon. The current mayor of Milford is...
in 1857. He attended
Drury High SchoolDrury High School is a school located in North Adams, Massachusetts. It serves the towns of Florida, North Adams, Readsboro, and Stamford.-History:1843 - School built with $3000 grant given by the late Nathan Drury, the school's namesake...
in
North Adams, MassachusettsNorth Adams is a city in Berkshire County, Massachusetts, United States. It is part of the Pittsfield, Massachusetts Metropolitan Statistical Area. The population was 14,681 at the 2000 census, making it the least populous city in the state...
and excelled in mathematics. In 1874, he won an appointment to the
United States Naval AcademyThe United States Naval Academy is an undergraduate college in Annapolis, Maryland, United States, that educates and commissions officers of the United States Navy and Marine Corps. The Academy often is referred to simply as "Annapolis". It is also called "The Academy", "The Boat School", or "Canoe...
in
Annapolis, MarylandAnnapolis is the capital of the U.S. state of Maryland, as well as the county seat of Anne Arundel County. It has a population of 36,524 , and is situated on the Chesapeake Bay at the mouth of the Severn River, south of Baltimore and about east of Washington D.C. Annapolis is part of the...
. There, he graduated seventh in the Class of 1878.
U.S. Navy, inventor
He was commissioned as an
ensignEnsign is a junior rank of commissioned officer in the militaries of some countries, normally in the infantry or navy. As the junior officer in an infantry regiment was traditionally the carrier of the ensign flag, the rank itself acquired the name....
in the U.S. Navy. During his ensuing naval service, he first served on the
USS RichmondThe USS Richmond was a wooden steam sloop in the United States Navy during the American Civil War.-Service in the Caribbean :Richmond was launched on 26 January 1860 by the Norfolk Navy Yard; sponsored by a Miss Robb. Richmond, commanded by Captain D. N. Ingraham, departed Norfolk, Virginia 13...
, then the
USS MinnesotaUSS Minnesota, a sailing/steam frigate, was launched in 1855 at the Washington Navy Yard and commissioned eighteen months later. She was decommissioned some five years later, but at the outbreak of the American Civil War, returned to service as the flagship of the North Atlantic Blockading...
. While his ship was in
Newport, Rhode IslandNewport is a city on Aquidneck Island in Newport County, Rhode Island, United States, about 30 miles south of Providence. Known as a New England summer resort and for the famous Newport Mansions, it is the home of Salve Regina University and Naval Station Newport which houses the United States...
, in 1881, Sprague invented the inverted type of
dynamo-In Engineering:* Dynamo, a magnetic device originally used as an electric generator* Dynamo theory, a theory relating to magnetic fields of celestial bodies* Solar dynamo, the physical process that generates the Sun's magnetic field-Europe:...
. After he was transferred to the
USS LancasterThe first USS Lancaster was a screw sloop-of-war in the United States Navy during the American Civil War through the Spanish-American War....
, flagship of the European Squadron, he installed the first electric call-bell system on a U.S. Navy ship. Sprague took leave to attend the Paris Electrical Exhibition in 1881 and the
Crystal PalaceDesigned by Joseph Paxton, the Great Exhibition building was long, with an interior height of .After the exhibition, the building was moved to a new park in a high, healthy and affluent area of London called Sydenham Hill, an area not much changed today from the well-heeled suburb full of large...
Exhibition in
SydenhamSydenham is a area and electoral ward in the London Borough of Lewisham; although some streets towards Crystal Palace Park and Penge are outside the ward and in the London Borough of Bromley, and some streets off Sydenham Hill are in the London Borough of Southwark. Sydenham was in Kent until 1889...
, England in 1882, where he was on the jury of awards for gas engines,
dynamo-In Engineering:* Dynamo, a magnetic device originally used as an electric generator* Dynamo theory, a theory relating to magnetic fields of celestial bodies* Solar dynamo, the physical process that generates the Sun's magnetic field-Europe:...
s and lamps.
Joining the emerging electrical industry
In 1883,
Edward H. JohnsonEdward Hibberd Johnson was an inventor and business associate of American inventor Thomas Alva Edison. He was involved in many of Edison's projects, and was a partner in an early organization which evolved into the General Electric Company, one of the largest Fortune 500 companies in the United...
, a business associate of
Thomas EdisonThomas Alva Edison was an American inventor, scientist and businessman who developed many devices that greatly influenced life around the world, including the phonograph, the motion picture camera, and a long-lasting, practical electric light bulb...
, persuaded Sprague to resign his naval commission to work for Edison. One of Sprague's significant contributions to the Edison Laboratory at Menlo Park, New Jersey was the introduction of mathematical methods. Prior to his arrival, Edison conducted many costly trial-and-error experiments. Sprague's approach was to calculate using mathematics the optimum parameters and thus save much needless tinkering. He did important work for Edison, including correcting Edison's system of mains and feeders for central station distribution. In 1884, he decided his interests in the exploitation of electricity lay elsewhere, and he left Edison to found the Sprague Electric Railway & Motor Company.
By 1886, Sprague's company had introduced two important inventions: a constant-speed, non-sparking motor with fixed brushes, and a method to return power to the main supply systems of equipment driven by electric motors. His new motor was the first to maintain constant revolutions per minute under different loads. It was immediately popular, and was endorsed by Edison as the only practical electric motor available. His method of returning power to main supply systems was important in the development of the electric train and the electric elevator.
Richmond: inventing the trolley-pole
Sprague's inventions included a system on streetcars for collecting electricity from overhead wires. His spring-loaded
trolley poleA trolley pole is a tapered cylindrical pole of wood or metal, used to transfer electricity from a "live" overhead wire to the control and propulsion equipment of a tram or trolley bus. The use of overhead wire in a system of current collection is reputed to be the 1880 invention of Frank J....
, invented in 1880, used a wheel to travel along the wire. In late 1887 and early 1888, using his trolley system, Sprague installed the first successful large electric street railway system, the
Richmond Union Passenger RailwayThe Richmond Union Passenger Railway, in Richmond, Virginia, was the first practical electric trolley system, and set the pattern for most subsequent electric trolley systems around the world. It is an IEEE milestone in engineering....
in
Richmond, VirginiaRichmond is the capital of the Commonwealth of Virginia, in the United States. Like all Virginia municipalities incorporated as cities, it is an independent city and not part of any county. Richmond is the center of the Richmond Metropolitan Statistical Area and the Greater Richmond area...
. Long a transportation obstacle, the hills of Richmond included grades of over 10%, and were an excellent proving ground for acceptance of his new technology in other cities, in contrast to the
cable carsA cable car or cable railway is a mass transit system using rail cars that are propelled by a continuously moving cable running at a constant speed. Individual cars stop and start by releasing and gripping this cable as required...
which climbed the steepest grades of Nob Hill in San Francisco at the time.
Within a year, electric power had replaced more costly
horsecarA horsecar was an animal-powered streetcar or tram.These early forms of public transport developed out of industrial haulage routes or from the omnibus that first ran on public streets in the 1820s, using the newly-invented iron or steel rail or 'tramway'...
s in many cities. By 1889 110 electric railways incorporating Sprague's equipment had been begun or planned on several continents. In 1890, Edison, who manufactured most of Sprague's equipment,
bought him outA buyout is an investment transaction by which an entire company or a controlling part of the stock of a company is sold. A firm "buys out" a company to take control of it. A buyout can take the form of a leveraged buyout, a venture capital buyout or a management buyout...
, and Sprague turned his attention to electric elevators.
Electric elevators
While electrifying the streetcars of Richmond, the increased passenger capacity and speed gave Sprague the notion that similar results could be achieved in vertical transportation: electric elevators. He saw that increasing the capacity of
elevatorAn elevator or lift is a vertical transport vehicle that efficiently moves people or goods between floors of a building...
shaft ways would not only save passengers' time, but would also increase the earnings of tall buildings, the heights of which were limited by the total floor space taken up in the shaft ways by slow-running hydraulic-powered elevators.
In 1892, Sprague founded the Sprague Electric Elevator Company, and with Charles R. Pratt developed the Sprague-Pratt Electric Elevator. The company developed floor control, automatic elevators, acceleration control of car safeties and a number of freight elevators. The Spague-Pratt
elevatorAn elevator or lift is a vertical transport vehicle that efficiently moves people or goods between floors of a building...
ran faster and with bigger loads than hydraulic or steam elevators, and 584 elevators had been installed worldwide. Sprague then sold his company to the
Otis Elevator CompanyThe Otis Elevator Company is the world's largest manufacturer of vertical transportation systems today, principally elevators and escalators. Founded in Yonkers, New York, USA in 1853 by Elisha Otis, the company pioneered the development of the safety elevator, invented by Otis, which used a...
in 1895.
Multiple unit train controls
Sprague's experience with elevator control led him to devise a
multiple unitMultiple-unit train control, sometimes abbreviated to multiple-unit or MU, is a method of simultaneously controlling all the traction equipment in a train from a single location, whether it be a number of self-powered cars or a set of locomotives.A set of vehicles under multiple unit control is...
system of electric railway operation, which accelerated the development of
electric tractionRailway electric traction describes the various types of locomotive and multiple units that are used on electrification systems around the world-History:...
. In the multiple unit system, each car of the train carries electric traction motors. By means of relays energized by train-line wires, the
engineerA railroad engineer, locomotive engineer, train operator, train driver or engine driver is a person who operates a railroad locomotive and train. The engineer is in charge of and responsible for the locomotive. They are also in charge of mechanical operation of the train, train speed, and all train...
(or
motormanA motorman is the person who operates an electrified trolley car, tram, light rail, or rapid transit train.The term refers to the person who is in charge of the motor in the same sense as a railroad engineer is in charge of the engine. The term was gender-neutral...
) commands all of the traction motors in the train to behave in unison. For lighter trains there is no need for
locomotiveA locomotive is a railway vehicle that provides the motive power for a train. The word originates from the Latin loco – "from a place", ablative of locus, "place" + Medieval Latin motivus, "causing motion", and is a shortened form of the term locomotive engine, first used in the early 19th...
s, so every car in the train can generate revenue; where locomotives are used, one person can control all of them.
Sprague's first multiple unit order was from the
South Side Elevated RailroadThe South Side Elevated Railroad was the first elevated rapid transit line in Chicago, Illinois. The line ran from downtown Chicago to Jackson Park, with branches to Englewood, Normal Park, Kenwood, and the Union Stock Yards...
(the first of several elevated railways in locally known as the
"L"The
'L' is a rapid transit system that serves the city of Chicago in the United States...
) in Chicago, Illinois. The success there was quickly followed by substantial multiple-unit contracts in Brooklyn, New York and Boston, Massachusetts.
New York: Grand Central, elevators in skyscrapers
From 1896 to 1900 Sprague served on the Commission for Terminal Electrification of the
New York Central RailroadThe New York Central Railroad , known simply as the New York Central in its publicity, was a railroad operating in the Northeastern United States...
, including the
Grand Central TerminalGrand Central Terminal — often popularly called Grand Central Station or simply Grand Central — is a terminal station at 42nd Street and Park Avenue in Midtown Manhattan in New York City...
in New York City, where he designed a system of automatic train control to ensure compliance with trackside signals. He founded the Sprague Safety Control & Signal Corporation to develop and build this system. Along with
William J. WilgusWilliam J. Wilgus was born in Buffalo, New York and graduated from Buffalo Central High School in 1883. Afterwards, Wilgus embarked on what would soon become a prominent career in civil engineering and did not earn a formal degree until much later in life. Wilgus worked on some of the largest and...
, he designed the Wilgus-Sprague bottom contact
third railA third rail is a method of providing electric power to a railway train, through a continuous rigid conductor placed alongside or between the rails of a railway track. It is used typically in a mass transit or rapid transit system, which has alignments in its own corridors, fully or almost fully...
system used by the railroads leading into Grand Central Terminal.
During
World War IWorld War I , also known as the First World War, the Great War, and the War to End All Wars, was a global military conflict which involved most of the world's great powers, assembled in two opposing alliances: the Triple Entente and the Triple Alliance...
, Sprague served on the Naval Consulting Board. Then, in the 1920s, he devised a method for safely running two independent elevators, local and express, in a single shaft, to conserve floor space. He sold this system, along with systems for activating elevator car safety systems when acceleration or speed became too great, to the Westinghouse Company.
Heritage, awards
The effect of Sprague's developments in electric traction was to permit an expansion in the size of cities, while his development of the elevator permitted greater concentration in cities' commercial sections and increased the profitability of commercial buildings. Sprague's inventions over 100 years ago made possible modern
light railLight rail or light rail transit is a form of urban rail public transportation that generally has a lower capacity and lower speed than heavy rail and metro systems, but higher capacity and higher speed than traditional street-running tram systems...
and
rapid transitA rapid transit, metro, subway, underground, or elevated railway system is an electric passenger railway in an urban area with high capacity and frequency, and which is grade separated from other traffic. Rapid transit systems are typically either in underground tunnels or elevated above street level...
systems which still function on the same principles today.
Sprague was awarded the gold medal at the Paris Electrical Exhibition in 1889, the grand prize at the St. Louis Exhibition in 1904, the
Elliott Cresson MedalThe Elliott Cresson Medal, also known as the Elliott Cresson Gold Medal, was the highest award given by the Franklin Institute. The award was established by Elliott Cresson, life member of the Franklin Institute, with $1,000 granted in 1848...
in 1904, the Edison Medal of the
American Institute of Electrical EngineersThe American Institute of Electrical Engineers was a United States based organization of electrical engineers that existed between 1884 and 1963...
, now IEEE, in 1910 'For meritorious achievement in electrical science, engineering and arts as exemplified in his contributions thereto', the
Franklin MedalThe Franklin Medal was a science and engineering award presented by the Franklin Institute, of Philadelphia, Pennsylvania, USA.-Laureates:*1915 - Thomas Alva Edison *1915 - Heike Kamerlingh Onnes *1916 - John J...
in 1921 and the John Fritz Gold Medal (posthumously) in 1935.
"All through his life and up to his last day, Frank Sprague had a prodigious capacity for work," his son Robert wrote in 1935. "And once having made up his mind on a new invention or a new line of work, he was tireless and always striving for improvement. He had a brilliantly alert mind and was impatient of any half-way compromise. His interest in his work never ceased; only a few hours before the end, he asked to have a newly designed model of his latest invention brought to his bedside."
Frank and Harriet Sprague had two sons, Robert and Julian. Robert founded the Sprague Electric Company which became a leading manufacturer of capacitors and other electronic components.
After Sprague died in 1934, his widow Harriet turned over a substantial amount of material from his collection to the
New York Public LibraryThe New York Public Library is one of the leading public libraries of the world and is one of the United States's most significant research libraries. It is composed of a very large circulating public library system combined with a very large non-lending research library system...
, where it remains today accessible to the public via the rare books division. He was buried at
Arlington National CemeteryArlington National Cemetery, in Arlington County, Virginia is a military cemetery in the United States, established during the American Civil War on the grounds of Arlington House, formerly the estate of the family of Robert E. Lee's wife Mary Anna Lee, a descendant of Martha Washington. The...
in Arlington, Virginia, and she was interred beside him after her death in 1969.
In 1959, Harriet Sprague had donated funds for the Sprague Building at the
Shore Line Trolley MuseumThe Shore Line Trolley Museum, located in East Haven, Connecticut, is the oldest operating trolley museum in the United States. It was founded to preserve the heritage of the trolley car. The museum encompasses the Branford Electric Railway Historic District, which was added to the U.S. National...
at
East Haven, ConnecticutEast Haven is a town in New Haven County, Connecticut, in the United States. As of the 2000 census, the town population was 28,189. The town is just 3 minutes from downtown New Haven...
, not far from Sprague's boyhood home in Milford. The museum is the oldest operating trolley museum in the United States, and has one of the largest collections of trolley artifacts in the United States.
In 1999, two of Frank and Harriet's grandsons, John L. Sprague and Peter Sprague, cut the ribbon and started an 1884 Sprague motor at a new exhibit at the Shore Line Trolley Museum. There, a permanent exhibit, "Frank J. Sprague: Inventor, Scientist, Engineer", helps tell the story of the part electricity played in the growth of cities as well as the role of the Father of Electric Traction. Entrepreneur Peter Sprague was Chairman of National Semiconductor from 1965 until 1995. John Sprague was President and Chief Executive Officer of Sprague Electric Company from 1981 to 1987.
External links