According to that model, light waves come in many sizes. The size of a wave is measured as its wavelength, which is the distance between any two corresponding points on successive waves, usually peak to peak or trough to trough. The wavelengths of the light we can see range from 400 to...
At the time, there were nearly 700,000 enslaved people living in the United States, worth many millions in today’s dollars. When the topic of slavery arose during the deliberations over calculating political representation in Congress, the southern states of Georgia and the Carolinas demanded ...
according to theRoyal Society of Chemistry. In the 1860s, Mendeleev was a popular lecturer at a university in St. Petersburg, Russia. At the time, no modern organic chemistry textbooks in the Russian language existed, so Mendeleev decided to write one. As he was working on that...
A year before, Oberlin College became the first higher-learning institution in the United States to admit women. Around that time, the exclusion of women in many abolitionist organizations prompted Elizabeth Cady Stanton and Lucretia Mott to rally together women -- and some men -- to ...
CS: And I think all the time about how that has become, in many ways, the sort of central animating framework or notion around how the world moves in my life, in which you can have two young people who are born into fundamentally different circumstances, who work equally as hard. And ...
The Pony Express was founded in 1860 by the Central Overland California and Pikes Peak Express (COC&PP), a freight company that supplied goods to the western part of the United States. COC&PP wanted the Butterfield Overland Mail Company's million-dollar government contract, so it set out to...
In studying these objects, I learned that Queen Victoria was known to have many beautiful holders. During a state visit to Paris for the Universal Exhibition of 1855, she received an enameled gold gem-encrusted holder from France’sEmpress Eugénie, ...
In 1728, William Byrd II led the first survey into the Great Dismal Swamp, to determine the Virginia/North Carolina boundary. He encountered a family of maroons, describing them as “mulattoes,” and was well aware that others were watching and hiding: “It is certain many Slaves Shelter ...
"Colorado Rockies” had been used by the hockey team of the same namefrom 1976to1982and was already somewhat known to the region. When fans were asked to chime in on the name of the new baseball team, many wantedthe Denver Bears(a former minor league team.) But...
Many credit Fredrick Guthrie as the first to synthesize mustard gas in 1860 , and Dow Chemical as the first company to produce it (during World War I) [source: Holland]. Mustard Gas in World War I British casualties blinded by mustard gas in a gas attack. Getty Images During World ...