Since the beginning of irrigated agriculture, it has been important to measure flows of irrigation water. Accuracy of early water measurement methods often suffered because of trash or sediment in the water, or unusual flow conditions. Ralph L. Parshall saw this problem when he began working for the USDA in 1915, as an irrigation research engineer. In 1922 he invented the flume now known by his name. When this flume is placed in a channel, flow is uniquely related to the water depth.
1985


The "Land Ordinance of 1785" required that U.S. lands in the public domain be surveyed before sale, and that the surveys be made in accordance with a consistent, integrated system of lines grid-oriented to a true meridian (north-south reference line) and base line (east-west reference line), subdividing the land into approximately square parcels, called townships.
Thomas Hutchins, the first Geographer of the United States, drove his stake near East Liverpool, Ohio to mark the Point of Beginning of the Geographer's Line, the first westward base line.

The Royal Colonial Boundary of 1665 was decreed by England's King Charles II to demarcate his American colonies. It provided a survey from the Atlantic Ocean to the Mississippi River along 36 degrees, 30 minutes north latitude. The boundary now serves to divide Virginia from North Carolina and Kentucky from Tennessee.

"The majestic Forth Bridge ... symbolises the tremendous achievements of Victorian engineers and the immense strides made in the technique of bridge design and construction since the dawn of the Railway Age..."
- Derrick Bennett, Bridges: Great Buildings of the World

Sculptor Frederic-Auguste Bartholdi is credited with bringing the concept of the Statue of Liberty to fruition, deriving inspiration from the 19th-century penchance for grandiose monuments. He originally designed the statue for placement at the Suez Canal, but the project was never commissioned. After a promotional trip across America, Bartholdi's ideas finally took hold in 1874, and a Franco-American coalition was formed to fund the project, with the Americans building the base and the French the statue.

In the 1850s, the Lexington and Danville Railroad began building a suspension bridge over the Kentucky River. The bridge was designed by John A Roebling. Due to unforeseen increases in train loads, the Roebling bridge was never completed. The High Bridge would then be built 20 years later on the existing foundations.



Considered one of the world's most scenic mountain drives, the two-lane Going-To-The-Sun Road through Glacier National Park was the first major road to be constructed directly over high mountain terrain, proving that roads did not need to be limited to mountain passes.

The concept of heating a number of buildings in the core area of a city from a single heating plant was introduced into the United States by Birdsill Holly at Lockport, New York, in 1877. The gain in thermal efficiency of a single large steam plant over a series of small isolated boilers led to widespread commercial installation of district heating. Organized by the Detroit Edison Company, the Central Heating Company began service here in 1903, supplying twelve customers with steam piped from the Edison Company's Willis Avenue Plant. Today's greatly enlarged system continues in operation.