An an odometer records the distance
that a vehicle travels. A speedometer measures the speed of a moving vehicle.
A tachometer indicates the speed of rotation of the engine.
According to Encyclopedia Britannia,
"About 15 BC, the Roman architect and engineer Vitruvius mounted a large
wheel of known circumference in a small frame, in much the same fashion
as the wheel is mounted on a wheelbarrow; when it was pushed along the
ground by hand it automatically dropped a pebble into a container at each
revolution, giving a measure of the distance traveled. It was, in effect,
the first odometer."
Chang Heng the inventor of the known
also invented an odometer that had a figure that struck a drum as each
li or 0.5 km went by to measure distance.
Pascal (1623 - 1662) invented a prototype of an odometer, a calculating
machine called a pascaline. The pasacaline was constructed of gears and
wheels. Each gear contained 10 teeth that when moved one complete revolution,
advanced a second gear one place. This is the same principal employed in
the mechanical odometer.
Thomas Savery - Odometer used
Savery (1650 - 1715) was an English military engineer and inventor
who in 1698, patented the first crude steam engine, among Savery's other
inventions was an odometer for ships, a device that measured distance traveled.
- Odometer used to Measure Postal Routes
Franklin (1706–1790) is best known as a statesman and writer, however
he was also an inventor who invented swim fins, bifocals, a glass armonica,
watertight bulkheads for ships, the lightning rod, a wood stove, and an
odometer. While serving as Postmaster General in 1775, Franklin decided
to analyze the best routes for delivering the mail. He invented a simple
to help measure the mileage of the routes that he attached to his carriage.
William Clayton, Orson Pratt,
Appleton Milo Harmon - Odometer called the Roadometer
An odometer called the “roadometer”
was invented in 1847 by the Morman pioneers crossing the plains from Missouri
to Utah. The roadometer attached to a wagon wheel and counted the revolutions
of the wheel as the wagon traveled. It was designed by William Clayton
and Orson Pratt, and built by carpenter Appleton Milo Harmon.
William Clayton was inspired to invent
the roadometer by his first method of recording the distance the pioneers
travelled each day. Clayton had determined that 360 revolutions of a wagon
wheel made a mile, he then tied a red rag to the wheel and counted the
revolutions to keep an accurate record of the mileage travelled. After
seven days, this method became tiresome and Clayton went on to invent the
roadometer, first used on the morning of May 12, 1847. William Clayton
is also known for his writing of the pioneer hymn "Come, Come, Ye Saints."
"I walked some this afternoon
in company with Orson Pratt and suggested to him the idea of fixing a set
of wooden cog wheels to the hub of a wagon wheel, in such order as to tell
the exact number of miles we travel each day. He seemed to agree with me
that it could be easily done at a trifling expense."
Samuel McKeen - Odometer used on
"Brother Appleton Harmon is working
at the machinery for the wagon to tell the distance we travel and expects
to have it in operation tomorrow, which will save me the trouble of counting,
as I have done, during the last four days."
"About noon today Brother Appleton
Harmon completed the machinery on the wagon called a 'roadometer' by adding
a wheel to revolve once in ten miles, showing each mile and also each quarter
mile we travel, and then casing the whole over so as to secure it from
the weather." ~ From William Clayton's Journal
In 1854, Samuel McKeen of Nova Scotia
designed an early version of the odometer, a device that measures mileage
driven. His was attached to the side of a carriage and measured the miles
with the turning of the wheels.
with >>> The
History of the Automobile