London, August 6 ANI: If you think that a major discovery is always named after its discoverer, here are five scientific breakthroughs for which wrong persons were credited. Back in 1885, the discovery of the bacterium, then known as Salmonella cholerae-suis, took place in the lab of Daniel Elmer Salmon, a major figure in veterinary medicine. The discovery was credited solely to Salmon despite the fact that he contributed nothing to the work: it was a result of the efforts of a young researcher named Theobald Smith, who isolated the bacterium while studying classical swine fever hog cholera in Salmon's lab.Another wrongly named discovery is Hansen's disease, commonly known as leprosy, which is so called in honour of the Norwegian physician Gerhard Armauer Hansen, who discovered the bacterium responsible for the condition.Though Hansen identified Mycobacterium leprae in 1873, he did not show that it was truly linked to leprosy.It was Albert Neisser, the discoverer of the gonorrhoea bacterium, who actually succeeded in staining the bacterium and, in 1880, announced that he had discovered the cause of leprosy.Infuriated, Hansen fought back with a lengthy article describing how his research had progressed since 1870, and was eventually given the credit following a decision taken at a conference on leprosy. According to a New Scientists magazine report, the two experts might have shared the credit, but Neisser's arrogant behaviour turned out to be the cause of his downfall in the end. Third wrongly named breakthrough was Benford's law, named after the optical physicist Frank Benford.The magazine report says that mathematician and astronomer Simon Newcomb had made this discovery about six decades before Benford. In 1881, Newcomb showed that, in lists of numbers drawn from real-life sources, the numbers are disproportionately likely to begin with the lower digits, particularly 1.He also put forward an equation describing the probability of a number starting with a given digit, although he did not have a good explanation for the strange fact.His discovery was subsequently forgotten for about 60 years, and was independently rediscovered in 1938 by Benford. Though Benford checked it against a great many data sets, an explanation eluded him too. The evidence Benford accumulated was enough to establish the law, and also to get it permanently associated with his name. Nevertheless, Newcomb unquestionably discovered it first.Next on the list is the Arrhenius equation, k = Ae-Ea/RT, which describes how the rate constant k of a chemical reaction varies with temperature T and the reaction's activation energy Ea. It is commonly called the Arrhenius equation after the Swedish chemist Svante Arrhenius, one of the key figures in physical chemistry, and the first person to predict that increasing levels of carbon dioxide in the atmosphere would cause global warming.However, it was first put forward by the Dutch chemist Jacobus Henricus van 't Hoff in 1884, in his book Studies in Chemical Dynamics based on studies of many different chemical reactions.Some five years later, Arrhenius provided a physical explanation for van 't Hoff's discovery when he came up with the concept of activation energy - the "kickstart" energy level that must be reached before a reaction can begin.He acknowledged van 't Hoff in his paper, but the equation nevertheless became indelibly linked to him. Fifth wrongly named discovery was Halley's comet, named after Edmond Halley.The comet itself had been observed as far back as 240 BC, by Chinese astronomers, and it is possible that even earlier sightings were made.Johannes Kepler certainly saw it in 1607, and Halley himself saw it in 1682, making some rough observations.Halley later realised the comet he had seen was extremely similar to comets seen in 1607 and 1531, and came to the conclusion that the comet was periodic - that it returned to the vicinity of Earth about every 76 years.He predicted when the comet would return, and when it came back in 1758, 16 years after his death, it became known as Halley's comet.The comet bears Halley's name not because he discovered it, but because he was the first to predict its behaviour. ANI