"There are but few special symbols in trigonometry, I... however add here... all that I have been able to learn... The current division of angles is derived from the Babylonians through the Greeks. The Babylonian unit angle was the angle of an ; following their usual practice... this was divided into sixty equal parts or degrees, a degree was subdivided into sixty equal parts or minutes, and so on. The word sine was used by and was derived from the Arabs: the terms secant and tangent were introduced by Thomas Finck... in his Geometriae Rotundi, Bâle, 1583: the word cosecant was (I believe) first used by Rheticus in his Opus Palatinum, 1596: the terms cosine and cotangent were first employed by E. Gunter in his Canon Triangulorum, London, 1620. The abbreviations sin, tan, sec were used in 1626 by , and those of cos and cot by Oughtred in 1657; but these contractions did not come into general use till Euler re-introduced them in 1748. The idea of trigonometrical functions originated with John Bernoulli, and this view of the subject was elaborated in 1748 by Euler in his Introductio in Analysin Infinitorum."