Duck Creek Aqueduct is a rare surviving example of a covered timber aqueduct. It was one of several similar structures on the Whitewater Canal, which operated between the Whitewater Valley and the Ohio River from 1839 to 1865. After being displaced by the railroad, the canal supplied hydraulic power for the industrial districts at Metamora and Brookville.
1840-1849

On July 14, 1848 in Baku, Azerbaijan, Major Alekseev supervised the completion of a 20+ meter well, reaching a small pocket of crude oil, thus establishing the world’s very first oil well. The process used was an archaic technique known as cable-tool drilling, employed for hundreds of years in ancient China. Major Alekseev acted under the instruction of governor-general Mikhail Semyonovich Vorontsov, who in a memo wrote:
Two immense side-wheel steamboats lined up a few minutes before 11:00 am on June 1, 1845 at the foot of Vesey Street on the tip of Manhattan. Inside each pilot house, some 30 feet above the water line, were the boats’ owners—industrialist Cornelius Vanderbilt and George Law—two immense egos who had decided to race 66 miles race upriver to Sing Sing. The gleaming tk-foot-long Cornelius Vanderbilt.
The Cincinnati Observatory, “The Birthplace of American Astronomy,” is the oldest professional observatory in the United States. Ormsby MacKnight Mitchel, the “Father of American Astronomy,” founded the observatory in 1842. John Quincy Adams laid the cornerstone for the observatory on Mt. Ida, later renamed Mt. Adams. The original Merz und Mahler 11-inch refractor telescope was put into service in 1845 and is still in use here today on Mount Lookout.
In February 1837, Treasury Secretary Levi Woodbury called for information from the “most intelligent sources” to help prepare a report to Congress on the propriety of establishing a “system of telegraphs” for the United States. Of the 18 responses he received, 17 assumed that the telegraph would be optical and its motive power human. The only respondent to envision a different operating force was Samuel F. B.

One of the earliest and most impressive of America's great railroad engineering feats, the Horseshoe Curve was built as a means of overcoming a straight-line grade over the geological feature known as the Allegheny Escarpment or Allegheny front, which separates the ridge-and-valley section of Pennsylvania (on the east) from the Allegheny Front (on the west). Such a straight-line route would have made commercial railroad operations unfeasible from both and economic and technical standpoint.

The Dublin to Belfast Rail Link established a vital connection between the capitals of Northern Ireland and the Republic of Ireland. The line's most notable engineering feature was the 1,760-foot-long Boyne Bridge; it represented one of the earliest uses of calculated stresses, the first large-scale use of wrought iron latticed girders, and the first full scale test of continuous beams. Tests performed on the wrought iron columns and struts were published and provided invaluable information for engineers who would design similar structures in the future.

By the turn of the 19th century, London's streets were clogged with traffic. Over 3,700 passengers used the Thames River's main boat crossing each day, while wagons and carts were forced to cross via the London Bridge, two miles away. Building a bridge would further impede shipping on the already-crowded Thames; a tunnel was the obvious alternative.
The first attempt at a tunnel in the present location began in 1807. The excavation had proceeded only 1,000 feet-using traditional mining methods-when crews reached a layer of quicksand and were forced to stop.

The Tennessee State Capitol, the first and only home of the Tennessee General Assembly, was designed by engineer and architect William Strickland. Since its construction, it has ably served, with little modification, as the seat of Tennessee's government.

The Starrucca Viaduct of the Erie Railroad Company crosses Starrucca Creek in Lanesboro, Pennsylvania. It is one of the oldest and one of the longest railroad bridges in Pennsylvania. Its 18 slender, semicircular stone arches each span 50 feet and the structure rises 110 feet above the creek.