Didymium (Greek: δίδυμο, twin) is a mixture of the elements praseodymium and neodymium.It is used in safety glasses for glassblowing and blacksmithing, especially with a gas ()-powered forge, where it provides a filter that selectively blocks the yellowish light at 589 nm emitted by the hot sodium in the glass without having a detrimental effect on general vision, unlike dark welder's ...

Early life. Christian Friedrich Samuel Hahnemann was born in Meissen, Saxony, near Dresden.His father Christian Gottfried Hahnemann was a painter and designer of porcelain, for which the town of Meissen is famous.. As a young man, Hahnemann became proficient in a number of languages, including English, French, Italian, Greek and Latin.

Arthrogryposis (AMC) describes congenital joint contracture in two or more areas of the body. It derives its name from Greek, literally meaning "curving of joints" (arthron, "joint"; grȳpōsis, late Latin form of late Greek grūpōsis, "hooking").Children born with one or more joint contractures have abnormal fibrosis of the muscle tissue causing muscle shortening, and therefore are …

Joshua Fry Speed (November 14, 1814 – May 29, 1882) was an American politician who was a close friend of future President Abraham Lincoln from his days in Springfield, Illinois, where Speed was a partner in a general store.Later, Speed was a farmer and a real estate investor in Kentucky, and also served one term in the Kentucky House of Representatives in 1848.

1841年1月琦善與查理·義律在清廷與英國政府不知情下草擬《穿鼻草約》，並於1月20日由義律發出《致女皇陛下臣民通函》。1月27日，義律提出「穿鼻條約」草案，其中一條是割讓香港島，要求照此訂約，琦善並未接受要求:8-9 。

James Braid (19 June 1795 – 25 March 1860) was a Scottish surgeon, natural philosopher, and "gentleman scientist".. He was a significant innovator in the treatment of clubfoot, spinal curvature, knock-knees, bandy legs, and squint; a significant pioneer of hypnotism and hypnotherapy, and an important and influential pioneer in the adoption of both hypnotic anaesthesia and chemical …

William Henry Harrison, né le 9 février 1773 à la plantation de Berkeley (colonie de Virginie) et mort le 4 avril 1841 à Washington, D.C., est un militaire, diplomate et homme d'État américain, 9 e président des États-Unis.. Après une carrière militaire et politique dans l'Ohio, il accède à la présidence à la suite de l'élection de 1840, à l'âge de 68 ans. Son mandat est ...

Louisiana (French: La Louisiane; La Louisiane française) or French Louisiana was an administrative district of New France.Under French control from 1682 to 1769 and 1801 (nominally) to 1803, the area was named in honor of King Louis XIV, by French explorer René-Robert Cavelier, Sieur de la Salle.It originally covered an expansive territory that included most …

Iver Johnson was born in 1841 in Nordfjord, Sogn og Fjordane county, Norway. He was educated as a gunsmith in Bergen in 1857, and had a gun store in Oslo.Johnson emigrated from Norway to Worcester, Massachusetts, United States in 1863, and continued his work as a gunsmith by trade and an inventor in his spare time.Seeking new and creative uses for his partially idle …