The Encyclopædia Britannica is a general knowledge English-language encyclopaedia. It is published by Encyclopædia Britannica, Inc.; the company has existed since the 18th century, although it has changed ownership various times through the centuries. The encyclopaedia is maintained by about 100 full-time editors and more than 4,000 contributors. The 2010 version of the 15th edition, which spans 32 volumes and 32,640 pages, was the last printed edition. Since 2011 it is being published exclusively as an online encyclopaedia.
The Encyclopædia Britannica Eleventh Edition (1910–1911), is a 29-volume reference work, an edition of the Encyclopædia Britannica. It was developed during the encyclopaedia's transition from a British to an American publication. Some of its articles were written by the best-known scholars of the time. This edition of the encyclopaedia, containing 40,000 entries, is now in the public domain, and many of its articles have been used as a basis for articles in Wikipedia. However, the outdated nature of some of its content makes its use as a source for modern scholarship problematic. Some articles have special value and interest to modern scholars as cultural artefacts of the 19th and early 20th centuries.
Henry Briggs was an English mathematician notable for changing the original logarithms invented by John Napier into common logarithms, which are sometimes known as Briggsian logarithms in his honour. The specific algorithm for long division in modern use was introduced by Briggs c. 1600 AD.
This article is a summary of the literary events and publications of 1631.
John Wallis was an English clergyman and mathematician who is given partial credit for the development of infinitesimal calculus. Between 1643 and 1689 he served as chief cryptographer for Parliament and, later, the royal court. He is credited with introducing the symbol ∞ to represent the concept of infinity. He similarly used 1/∞ for an infinitesimal. John Wallis was a contemporary of Newton and one of the greatest intellectuals of the early renaissance of mathematics.
The multiplication sign, also known as the times sign or the dimension sign, is the symbol ×, used in mathematics to denote the multiplication operation and its resulting product. While similar to a lowercase X, the form is properly a four-fold rotationally symmetric saltire.
The plus–minus sign, ±, is a mathematical symbol with multiple meanings.
The year 1631 in science and technology involved some significant events.
William Oughtred, also Owtred, Uhtred, etc., was an English mathematician and Anglican clergyman. After John Napier invented logarithms and Edmund Gunter created the logarithmic scales upon which slide rules are based, Oughtred was the first to use two such scales sliding by one another to perform direct multiplication and division. He is credited with inventing the slide rule in about 1622. He also introduced the "×" symbol for multiplication and the abbreviations "sin" and "cos" for the sine and cosine functions.
John Pell was an English mathematician and political agent abroad.
Censorinus was a Roman grammarian and miscellaneous writer from the 3rd century AD.
The history of logarithms is the story of a correspondence between multiplication on the positive real numbers and addition on the real number line that was formalized in seventeenth century Europe and was widely used to simplify calculation until the advent of the digital computer. The Napierian logarithms were published first in 1614. E. W. Hobson called it "one of the very greatest scientific discoveries that the world has seen." Henry Briggs introduced common logarithms, which were easier to use. Tables of logarithms were published in many forms over four centuries. The idea of logarithms was also used to construct the slide rule, which became ubiquitous in science and engineering until the 1970s. A breakthrough generating the natural logarithm was the result of a search for an expression of area against a rectangular hyperbola, and required the assimilation of a new function into standard mathematics.
Events from the year 1631 in England.
Thomas Wharton (1614–1673) was an English physician and anatomist best known for his descriptions of the submandibular duct and Wharton's jelly of the umbilical cord.
The Hobbes–Wallis controversy was a polemic debate that continued from the mid-1650s well into the 1670s, between the philosopher Thomas Hobbes and the mathematician John Wallis. It was sparked by De corpore, a philosophical work by Hobbes in the general area of physics. The book contained not only a theory of mathematics subordinating it to geometry and geometry to kinematics, but a claimed proof of the squaring of the circle by Hobbes. While Hobbes retracted this particular proof, he returned to the topic with other attempted proofs. A pamphleteering exchange continued for decades. It drew in the newly formed Royal Society, and its experimental philosophy to which Hobbes was opposed.
Gilbert Clerke (1626–c.1697) was an English mathematician, natural philosopher and Socinian theological writer.
Robert Wood or Woods (1622?–1685) was an English mathematician.
Richard Delamaine or Delamain, known as the elder, was an English mathematician, known for works on the circular slide rule and sundials.
Frederick Hockley was a British occultist and scryer who was a London-based Freemason and a member of the Societas Rosicruciana in Anglia.
William Forster was an English mathematician, known for publishing a book describing inventions of William Oughtred.
