Automobiles revolutionized dating 20th century
He joined a team led by Thomas Edison, who had been working on his "grasshopper telegraph" for trains, and together they constructed on the Lehigh Valley Railroad one of the only induction telegraph systems ever put to commercial use.
Although this telegraph was a technical success, it fulfilled no public need, and the market for on-board train telegraphy never took off.
Most interesting were the reasons they made their choices.
When myths go unchallenged for too long, they begin to eclipse the truth. Although this page does not cover every dubious invention claim floating around out there, it should at least serve as a warning never to take any such claim for granted. Designed by JP Knight, it featured two semaphore arms and two gas lamps.Each item below is listed with its supposed black originator beneath it along with the year it was supposedly invented, followed by something about the real origin of the invention or at least an earlier instance of it. The earliest traffic lights include Lester Wire's two-color version set up in Salt Lake City circa 1912, James Hoge's system (US patent #1,251,666) installed in Cleveland by the American Traffic Signal Company in 1914, and William Potts' 4-way red-yellow-green lights introduced in Detroit beginning in 1920.New York City traffic towers began flashing three-color signals also in 1920. Research by Barry Mackintosh, who served as bureau historian for the National Park Service (which manages the G. Carver National Monument), demonstrated the following: " arose to distinguish Elijah's inventions from cheap imitations? The oil cup, which automatically delivers a steady trickle of lubricant to machine parts while the machine is running, predates Mc Coy's career; a description of one appears in the May 6, 1848 issue of . Robertson of the US army preserved blood in a citrate-glucose solution and stored it in cooled containers for later transfusion. By the mid-1930s the Russians had set up a national network of facilities for the collection, typing, and storage of blood.Evidence of modern peanut butter comes from US patent #306727 issued to Marcellus Gilmore Edson of Montreal, Quebec in 1884, for a process of milling roasted peanuts between heated surfaces until the peanuts reached "a fluid or semi-fluid state." As the product cooled, it set into what Edson described as "a consistency like that of butter, lard, or ointment." In 1890, George A. Louis, manufactured peanut butter and sold it out of barrels. Variants of the phrase appear in Scottish literature dating back to at least 1856 — well before Elijah Mc Coy could have been involved. Did Charles Drew "discover" (in about 1940) that plasma could be separated and stored apart from the rest of the blood, thereby revolutionizing transfusion medicine? The possibility of using blood plasma for transfusion purposes was known at least since 1918, when English physician Gordon R. In the mid-1930s, John Elliott advanced the idea, emphasizing plasma's advantages in shelf life and donor-recipient compatibility, and in 1939 he and two colleagues reported having used stored plasma in 191 transfusions. Pierre-Charles L'Enfant created the layout of Washington DC.Detailed evidence: The not-so-real Mc Coy Also see The Fake Mc Coy and Did Somebody Say Mc Trash? (See historical notes on plasma use.) Charles Drew was not responsible for any breakthrough scientific or medical discovery; his main career achievement lay in supervising or co-supervising major programs for the collection and shipment of blood and plasma. Banneker assisted Andrew Ellicott in the survey of the federal territory, but played no direct role in the actual planning of the city.