Dichlorodiphenyltrichloroethane known as DDT, is a colorless and odorless crystalline chemical compound, an organochlorine. Developed as an insecticide, it became infamous for its environmental impacts. DDT was first synthesized in 1874 by the Austrian chemist Othmar Zeidler. DDT's insecticidal action was discovered by the Swiss chemist Paul Hermann Müller in 1939. DDT was used in the second half of World War II to control malaria and typhus among civilians and troops. Müller was awarded the Nobel Prize in Physiology or Medicine in 1948 "for his discovery of the high efficiency of DDT as a contact poison against several arthropods". By October 1945, DDT was available for public sale in the United States. Although it was promoted by government and industry for use as an agricultural and household pesticide, there were concerns about its use from the beginning. Opposition to DDT was focused by the 1962 publication of Rachel Carson's book Silent Spring, it cataloged environmental impacts that coincided with widespread use of DDT in agriculture in the United States, it questioned the logic of broadcasting dangerous chemicals into the environment with little prior investigation of their environmental and health effects.

The book said that DDT and other pesticides had been shown to cause cancer and that their agricultural use was a threat to wildlife birds. Its publication was a seminal event for the environmental movement and resulted in a large public outcry that led, in 1972, to a ban on DDT's agricultural use in the United States. A worldwide ban on agricultural use was formalized under the Stockholm Convention on Persistent Organic Pollutants, but its limited and still-controversial use in disease vector control continues, because of its effectiveness in reducing malarial infections, balanced by environmental and other health concerns. Along with the passage of the Endangered Species Act, the United States ban on DDT is a major factor in the comeback of the bald eagle and the peregrine falcon from near-extinction in the contiguous United States. DDT is similar in structure to the acaricide dicofol, it is hydrophobic and nearly insoluble in water but has good solubility in most organic solvents and oils.

DDT does not occur and is synthesised by consecutive Friedel–Crafts reactions between chloral and two equivalents of chlorobenzene, in the presence of an acidic catalyst. DDT has been marketed under trade names including Anofex, Chlorophenothane, Dinocide, Guesapon, Gyron, Neocid and Zerdane. Commercial DDT is a mixture of several closely–related compounds. Due to the nature of the chemical reaction used to synthesize DDT, several combinations of ortho and para arene substitution patterns are formed; the major component is p' isomer. The o,p' isomeric impurity is present in significant amounts. Dichlorodiphenyldichloroethylene and dichlorodiphenyldichloroethane make up the balance of impurities in commercial samples. DDE and DDD are the major metabolites and environmental breakdown products. DDT, DDE and DDD are sometimes referred to collectively as DDX. Components of commercial DDT DDT has been formulated in multiple forms, including solutions in xylene or petroleum distillates, emulsifiable concentrates, water-wettable powders, aerosols, smoke candles and charges for vaporizers and lotions.

From 1950 to 1980, DDT was extensively used in agriculture – more than 40,000 tonnes each year worldwide – and it has been estimated that a total of 1.8 million tonnes have been produced globally since the 1940s. In the United States, it was manufactured by some 15 companies, including Monsanto, Montrose Chemical Company and Velsicol Chemical Corporation. Production peaked in 1963 at 82,000 tonnes per year. More than 600,000 tonnes were applied in the US before the 1972 ban. Usage peaked in 1959 at about 36,000 tonnes. In 2009, 3,314 tonnes were produced for malaria visceral leishmaniasis. India is the only country still manufacturing DDT, is the largest consumer. China ceased production in 2007. In insects, DDT opens sodium ion channels in neurons, causing them to fire spontaneously, which leads to spasms and eventual death. Insects with certain mutations in their sodium channel gene are resistant to DDT and similar insecticides. DDT resistance is conferred by up-regulation of genes expressing cytochrome P450 in some insect species, as greater quantities of some enzymes of this group accelerate the toxin's metabolism into inactive metabolites.

Genomic studies in the model genetic organism Drosophila melanogaster revealed that high level DDT resistance is polygenic, involving multiple resistance mechanisms. DDT was first synthesized in 1874 by Othmar Zeidler under the supervision of Adolf von Baeyer, it was further described in 1929 in a dissertation by W. Bausch and in two subsequent publications in 1930; the insecticide properties of "multiple chlorinated aliphatic or fat-aromatic alcohols with at least one trichloromethane group" were described in a patent in 1934 by Wolfgang von Leuthold. DDT's insecticidal properties were not, discovered until 1939 by the Swiss scientist Paul Hermann Müller, awarded the 1948 Nobel Prize in Physiology and Medicine for his efforts. DDT is the best-known of several chlorine-containing pesticides used in the 1950s. With pyrethrum in short supply, DDT was used extensively during World War II by the Allies to control the insect vectors of typhus – nearly eli

Eliza Marian Butler, who published as E. M. Butler and Elizabeth M. Butler, was an English scholar of German, Schröder Professor of German at the University of Cambridge from 1945, her most influential book was The Tyranny of Greece over Germany, in which she wrote that Germany has had "too much exposure to Ancient Greek literature and art. The result was that the German mind had succumbed to'the tyranny of an ideal'; the German worship of Ancient Greece had emboldened the Nazis to remake Europe in their image." It was controversial in Britain and its translation was banned in Germany. Eliza Butler, known as "Elsie", was born in Lancashire in a family of Irish ancestry, she was educated by a Norwegian governess and subsequently in Hannover from age 11, Paris from age 15, the school of domestic science at Reifenstein Abbey from age 18, Newnham College, Cambridge from 21. As a teenager, she watched. In the First World War she worked as an interpreter and nurse in Scottish units on the Russian and Macedonian fronts and treated the victims of the German assault.

From 1926 to her death Butler travelled with her companion Isaline Blew Horner. After working in hospitals, she taught at Cambridge and in 1936 became a professor at the University of Manchester, her works include a trilogy on ritual magic and the occult in the Faust legend. Butler wrote novels, her autobiography, Paper Boats, was published by William Collins, Sons in 1959, the year of her death. She died in London on 13 November 1959, she may have inspired the scholar Suzanne L. Marchand to research German Orientalism, as Marchand emphasized the political overtones of Orientalistik, in reaction to Edward Said's assumption that Germany has had a "classical" interest in the Orient; the Saint-Simonian Religion The Tempestuous Prince The Tyranny of Greece Over Germany: A Study of the Influence Exercised by Greek Art and Poetry Over the Great German Writers of the Eighteenth and Twentieth Centuries. Rainer Maria Rilke The Myth of the Magus Ritual Magic; the Fortunes of Faust The Pennsylvania State University Press, 1952.

Paper Boats, a volume of reminiscences Eliza Marian Butler at The Peerage

Hollow Horn Bear was a Brulé Lakota leader. He fought including the Battle of Little Big Horn; as police chief of the Rosebud Indian Reservation, he arrested Crow Dog for the murder of Spotted Tail, testified in the case of Ex parte Crow Dog, argued before the Supreme Court of the United States. He was the chief orator and negotiator for the Lakota, making multiple trips to Washington, D. C. to advocate on their behalf, taking part in the inaugural parades for both Theodore Roosevelt and Woodrow Wilson. He died of pneumonia in Washington after the last of these trips, he was featured on a 1970 $10 Military Payment Certificate. Some sources record him as the basis for the image on the 1899 US five-dollar silver certificate and other depictions of Native Americans. A historical marker was erected in his honor in South Dakota in 1962. Hollow Horn Bear was born in modern Sheridan Nebraska. Named for his grandfather, he was one of seven sons of Chief Iron Shell, his mother was Wants Everything. During the Battle of Ash Hollow, he was a child and captive along with his mother at Fort Laramie, until they were released in October 1855.

Hollow Horn Bear took part in 31 battles of the Sioux Wars. He was involved in his first battle at age 12. At age 16 he and his father fought the Pawnee near present day Genoa, as a teenager he participated in raids against settlers and miners across the present day states of Montana and North and South Dakota, he went on to fight against the US Army in Wyoming and near present day Crow Agency, in 1869, in actions against those constructing the Union Pacific Railroad. In 1874 Hollow Horn Bear married Good Bed with; the same year he began working with the US Army as a scout. In 1876 Hollow Horn Bear was with a band of Two Kettles Lakota searching for lost horses, when they happened upon a group of soldiers under the command of Alfred Terry. After two days of following Terry's men, they broke off and went ahead of the column to meet with camp of those under Sitting Bull. After five days there they took part in the Battle of the Little Bighorn. For his part, Hollow Horn Bear claimed to have there fought against Marcus Reno as well as George Armstrong Custer.

In 1880 he traveled to Washington, D. C. to discuss issues regarding the reservation with the US government. Hollow Horn Bear was appointed the head of police of the Rosebud Agency in South Dakota, as part of the Indian Police organized by the Bureau of Indian Affairs, he arrested Crow Dog for the murder of Spotted Tail on August 5, 1881. Testifying in 1883 at the trial in Ex parte Crow Dog, Hollow Horn Bear recounted: Mr. Lelar gave me a paper for the arrest of Crow Dog. Found defendant on a hill between White River and Rosebud Creek, where I made the arrest. Defendant had no clothes at the time, except a blanket and leggings and was on horseback. I took defendant to Fort Niobara. Once found, Hollow Horn Bear testified he told Crow Dog he "wanted him to go with me to the post", to which he and Black Crow, with him at the time, agreed. Hollow Horn Bear had been a long time friend of Crow Dog, testified he had attended his wedding when he was nine years old; the case, argued before the US Supreme Court, became an important milestone in federal legal dealings with tribes, contributed to the passage of the 1885 Major Crimes Act.

Hollow Horn Bear resigned the position as head of police five years due to illness. Hollow Horn Bear was an advocate for the Lakota throughout repeated negotiations from 1890 to 1910. Although as one source put it, he was unable "to prevent the government from violating the 1868 treaty", his "presence at the negotiations pushed the agreements in the direction of Lakota interests", without which "things would have been much worse" for them. In 1895 he was arrested over a dispute involving reduction of wages paid to members of his tribe who were working for the railroad. Wages were cut by half, although at the time of his arrest, this had been lowered to a reduction of 35%; the New York Times report summarized the tension saying: Hollow Horn Bear appears to have an excellent record, extending back nearly twenty years. Col. Guy V. Henry is quoted as saying, in view of his services in 1876 and again in 1890, consideration should have been shown him unless he had committed some grievous fault more than the reports from that region have indicated.

Still, threatening to burn the agency buildings and summoning large bodies of Indians to intimidate the agent must be accounted a grievous fault... In 1889 he was chosen to represent his tribe in negotiations with George Crook, over land sales aimed at opening up eastern parts of the Dakota Territory to the Black Hills, he was an opponent of the selling of native lands in the Black Hills as part of the Black Hills Land Claim dispute. He instead wished to sell land in modern day Gregory and Tripp counties in South Dakota, which "he saw as worthless prairie lands in comparison to the rich Black Hills." He believed that individual ownership of land would protect his people while held land would "always be open to unilatral annexation by Congress". The US government had earlier made the decision to improve their offer from the previous $1.00 per acre to $1.25, 160 acres to 320 acres of land for homesteads to the family heads, provide horses for plowing rather than oxen. Hollow Horn Bear asked instead for $1.50 for the best land.

As reported by The Brooklyn Daily Eagle, Hollow Horn Bear was part of a delegation to Washington, D. C. in 1891, which met with Secretary of the Interior John Willock Noble. According