The son of Benjamin Oughtred ofEton inBuckinghamshire (now part ofBerkshire), William was born there on 5 March 1574/75 and was educated atEton College, where his father, a writing-master, was one of his teachers.[7] Oughtred had a passion for mathematics, and would often stay awake at nights to learn while others were sleeping.[8] He then attendedKing's College, Cambridge, where he graduated BA in 1596/97 and MA in 1600, holding a fellowship in the college from 1595 to 1603.[9] He composed a Funeral Ode in Latin for SirWilliam More ofLoseley Park in 1600.[10]
On 20 February 1606, at Shalford, Oughtred married Christs-gift Caryll, a relation of the Caryll family seated at Great Tangley Hall at Shalford.[13][14][15] The Oughtreds had twelve children, William,[16] Henry, Henry (the first Henry died as a baby), Benjamin, Simon, Margaret, Judith, Edward, Elizabeth, Anne, George, and John. Two of the sons, Benjamin and John, shared their father's interest in instruments and became watchmakers.[17]
Oughtred's wife was a cousin of Simon Caryll of Tangley and his wife Lady Elizabeth Aungier (married 1607), daughter ofSir Francis Aungier. Oughtred was a witness to Simon Caryll's will, made 1618,[18][19] and through two further marriages Elizabeth remained matriarch and dowager of Great Tangley until her death in about 1650.[20][21] Elizabeth's brother Gerald, 2nd Baron Aungier of Longford, was married to Jane, daughter of SirEdward Onslow ofKnowle, Surrey, in 1638. Oughtred praised Gerald (whom he taught) as a man of great piety and learning, skilled in Latin, Greek, Hebrew and other oriental languages.[22][23]
In January 1610 SirGeorge More, patron ofCompton church adjacent toLoseley Park, granted theadvowson (right of presentation of the minister) to Oughtred, when it should next fall vacant, though Oughtred was not thereby empowered to present himself to the living.[24] This was soon after Sir George More became reconciled to the marriage of his daughter Anne to the poetJohn Donne, which had occurred secretly in 1601.
Oughtred was presented by Sir Edward Randyll ofChilworth (lord of the manor) to the rectory ofAlbury, nearGuildford in Surrey and instituted on 16 October 1610,[25] vacating Shalford on 18 January 1611.[26]
In January 1615/16 Sir George More re-granted the advowson of Compton church (still occupied) in trust to Roger Heath and Simon Caryll, to present Oughtred himself, or any other person whom Oughtred should nominate, when the vacancy should arise.[27] Soon afterwards Oughtred was approached by John Tichborne seeking his own nomination, and entering an agreement to pay him a sum of money upon certain days. Before this could be completed the incumbent died (November 1618), and Oughtred sought for himself to be presented, preaching several times at Compton, having thefirst fruits sequestered to his use, and, after four months, asking the patron to present him. However, Tichborne offered to complete the agreed payment at once, and was accordingly presented by the trustees in May 1619 (Simon Caryll dying in that year): but before he could be admitted, the Crown interposed a different candidate because the contract between Oughtred and Tichborne was deemed by SirHenry Yelverton clearly to beSimoniacal.[24]
Oughtred therefore remained at Albury,[28] serving asrector there for fifty years.[29][30] His patron, theEarl of Arundel, acquired the fine old seat of Albury House through trustees in 1638: title to the manor was assigned in trust for payment of debts to George Duncombe (of Weston in Albury, embedded in the Carrill and Onslow interests), who maintained the manorial courts until his death in 1646, and then to Duncombe's children.[31] The Park and landscapes,[32] which formed the subject of a series of etchings produced byWenceslas Hollar, c. 1645,[33] were developed in this period, before aparliamentary sequestration which was eventually discharged in 1653.[31] The Earl having died in 1646, andhis son and successor Henry (who renewed the assignment) in 1652, it was the grandsonHenry Howard (later Duke of Norfolk) who finally paid for and acquired Albury.[34]
William Lilly, that celebrated astrologer, knew Oughtred and claimed in his autobiography to have intervened on his behalf to prevent his ejection from his living by Parliament in 1646:
"About this time, the most famous mathematician of all Europe, Mr. William Oughtred, parson of Aldbury in Surry, was in danger ofsequestration by theCommittee of or for plundered ministers; (Ambo-dexters they were;)[35] several inconsiderable articles were deposed and sworn against him, material enough to have sequestered him, but that, upon his day of hearing, I applied myself to SirBolstrode Whitlock, and all my own old friends, who in such numbers appeared in his behalf, that though the chairman and many other Presbyterian members were stiff against him, yet he was cleared by the major number."[36]
Of his portrait (aged 73, 1646) engraved by Wenceslas Hollar, prefixed to theClavis Mathematica,John Evelyn remarked that it "extreamly resembles him", and that it showed "that calm and placid Composure, which seemed to proceed from, and be the result of some happyἕυρησις and Invention".[37] William Oughtred died at Albury in 1660, a month after the restoration ofCharles II. A staunch supporter of the royalty, he is said to have died of joy at the knowledge of the return of the King. He was buried inOld St Peter and St Paul's Church, Albury.[38] Autobiographical information is contained in his address "To the English gentrie" in hisJust Apologie of c. 1634.[39]
Oughtred developed his interest in mathematics early in life, and devoted whatever spare time his academic studies allowed him to it. Among the short tracts added to the 1647/48 editions of theClavis Mathematica was one describing a natural and easy way of delineating sun-dials upon any surface, however positioned, which the author states he invented in his 23rd year (1597/98), which is to say, during his fellowship atKing's College, Cambridge. His early preoccupation was to find a portable instrument or dial by which to find the hour, he tried various contrivances, but never to his satisfaction. "At last, considering that all manner of questions concerning the first motions were performed most properly by the Globe itself, rectified to the present elevation by the help of a moveableAzimuth; he projected the Globe upon the plane of the Horizon, and applied to it at the center, which was therein theZenith, an Index with projected degrees, for the moveable Azimuth."[2]
An instrument for Oughtred's "Circles of Proportion", by Elias Allen, c. 1633–1640 (Harvard University, Putnam Gallery)
This projection answered his search, but then he had to invent theorems, problems and methods to calculate sections and intersections of large circles, which he could not find by instruments, not having access to any of sufficient size. In this way he drew out his findings, presenting one example to BishopThomas Bilson (who had ordained him), and another, in about 1606, to a certain noble lady, for whom he wrote notes for its use. In London, in spring 1618, Oughtred visited his friendHenry Briggs atGresham College, and was introduced toEdmund Gunter, Reader in Astronomy, then occupying Dr Brooks's rooms. He showed Gunter his "Horizontall Instrument", who questioned him closely about it and spoke very approvingly. Soon afterwards Gunter sent him a print taken from a brass instrument made byElias Allen, after Oughtred's written instructions (which Allen preserved).[2] When, in 1632,Richard Delamain the elder claimed that invention for himself,[40][41] William Robinson wrote to Oughtred: "I cannot but wonder at the indiscretion of Rich. Delamain, who being conscious to himself that he is but the pickpurse of another man's wit, would thus inconsiderately provoke and awake a sleeping lion..."[42]
Around 1628 he was appointed by theEarl of Arundel to instruct his son William Howard in mathematics.[28] Some of Oughtred's mathematical correspondence survives, and is printed inBayle'sGeneral Dictionary,[2] and (with some editorial omissions restored) inRigaud'sCorrespondence of Scientific Men.[43]William Alabaster wrote to him in 1633 to propose the quadrature of the circle by consideration of the fourth chapter of theBook of Ezekiel.[44] In 1634 he corresponded with the French architectFrançois Derand, and (among others) withSir Charles Cavendish (1635),Johannes Banfi Hunyades (1637),William Gascoigne (1640)[45] and Dr John Twysden, M.D. (1650).[46]
Oughtred offered free mathematical tuition to pupils, among themRichard Delamain andJonas Moore, and his teaching influenced a generation of mathematicians.Seth Ward resided with Oughtred for six months to learn contemporary mathematics, and the physicianCharles Scarborough also stayed at Albury:John Wallis andChristopher Wren corresponded with him.[47] Another Albury pupil wasRobert Wood, who helped him to see theClavis through the press.[48]Isaac Newton's high opinion of Oughtred is expressed in his letter of 1694 to Nathaniel Hawes, where he quotes him extensively, calling him "a Man whose judgement (if any man's) may safely be relyed upon... that very good and judicious man, Mr Oughtred".[49]
The first edition of John Wallis's foundational text oninfinitesimal calculus,Arithmetica Infinitorum (1656), carries a long letter of dedication to William Oughtred.[50]
William Oughtred's most important work was first published in 1631, in Latin, under the titleArithemeticæ in Numeris et Speciebus Institutio, quae tum Logisticæ, tum Analyticæ, atque adeus totius Mathematicæ quasi Clavis est (i.e. "The Foundation of Arithmetic in Numbers and Kinds, which is as it were the Key of the Logistic, then of the Analytic, and so of the whole Mathematic(s)"). It was dedicated toWilliam Howard, youngest son of Oughtred's patronThomas Howard, 14th Earl of Arundel.[51]
Clavis mathematicae, 1652 edition
This is a textbook on elementary algebra. It begins with a discussion of the Hindu-Arabic notation of decimal fractions and later introduces multiplication and division sign abbreviations of decimal fractions. Oughtred also discussed two ways to perform long division and introduced the "~" symbol, in terms of mathematics, expressing the difference between two variables.Clavis Mathematicae became a classic, reprinted in several editions. It was used as a textbook byJohn Wallis andIsaac Newton among others. A concise work, it argued for a less verbose style in mathematics, and greater dependence on symbols. Drawing onFrançois Viète (though not explicitly), Oughtred also innovated freely with symbols, introducing not only the multiplication sign as now used universally,[52] but also theproportion sign (double colon ::).[53] The first edition, 1631, contained 20 chapters and 88 pages including algebra and various fundamentals of mathematics.[54]
The work was recast for theNew Key, which appeared first in an English edition of 1647,The Key of the Mathematicks New Forged and Filed, dedicated to SirRichard Onslow and to his sonArthur Onslow (son and grandson of Sir Edward), and then in a Latin edition of 1648, entitledClavis Mathematica Denuo Limata, sive potius Fabricata (i.e. "The Mathematical Key Newly Filed, or rather Made"), in which the preface was removed and the book was reduced by one chapter. In the English Foreword, Oughtred explains that the intention had always been to provide the ingenious reader with anAriadne's thread through the intricate labyrinth of these studies, but that his earlier, highly compressed style had been found difficult by some, and was now further elucidated.[55] These editions contained additional tracts on the resolution of adfected equations proposed in numbers, and other materials necessary for the use of decimal parts and logarithms, as well as his work on delineating sundials.[56]
The last lifetime edition (third) was in 1652, and posthumous editions (asClavis Mathematicæ: i.e. "The Key of Mathematic(s)") appeared in 1667 and 1693 (Latin), and in 1694 (English). The work gained popularity around 15 years after it first appeared, as mathematics took a greater role in higher education. Wallis wrote the introduction to his 1652 edition, and used it to publicise his skill ascryptographer;[57] in another, Oughtred promoted the talents of Wren.
The Circles of Proportion and the Horizontal Instrument (1632)
Arundel House, (above), looking south; (below), looking north.[58] By Adam Bierling with Wenceslas Hollar, 1646.
This work[59] was used by Oughtred inmanuscript before it was edited for publication by his pupil,William Forster.[60] Here Oughtred introduced the abbreviations fortrigonometric functions. It contains his description and instructions for the use of his important invention, theslide rule, a mechanical means of finding logarithmic results.[61]
Two of Oughtred's students, William Forster andRichard Delamaine the elder, are concerned with the story of this book.[62] As instructor to the Earl of Arundel's son, Oughtred had the use of a room inArundel House, the Earl's residence in theStrand, in London. He gave free instruction there to Richard Delamaine, whom he found to be too dependent on mathematical instruments to get a proper grasp of the theory behind them. Another student of his, Forster, who came to him as a beginner during the 1620s, was therefore taught without reference to instruments so that he should have a true grounding.[63] However, during the long vacation of 1630 Forster (who taught mathematics from a house inSt Clement Danes churchyard, on the Westminster side ofTemple Bar, in the same locality as Elias Allen's shop), while staying with Oughtred at Albury, asked him about Gunter's Ruler, and was shown two instruments used by his master, including Oughtred's circular slide rule.[64]
Elias Allen, by Hollar: Oughtred's instrument-maker
Oughtred then said to Forster:
"... the true way of Art is not by Instruments, but by Demonstration: and ... it is a preposterous course of vulgar Teachers, to begin with Instruments, and not with the Sciences, and so in-stead of Artists, to make their Schollers only doers of tricks, and as it were Iuglers: to the despite of Art, losse of precious time, and betraying of willing and industrious wits, unto ignorance, and idlenesse. ... the use of Instruments is indeed excellent, if a man be an Artist: but contemptible, being set and opposed to Art. And lastly, ... he meant to commend to me, the skill of Instruments, but first he would have me well instructed in the Sciences."[64]
Forster obtained Oughtred's permission to translate, edit and publish the description, explanations and instructions which Oughtred had in manuscript, finishing his work in 1632.[64] Meanwhile Delamaine, who had also been shown the instruments, and had copied a text sent by Oughtred to his instrument-makerElias Allen, was writing-up his own description and account. Delamaine came off the press first, in two separate tracts,[65] claiming himself to be the inventor, and dedicating the prior treatise to KingCharles I. He went so far as to show his page-proofs to Oughtred as they were being prepared, and dismissed his objections,[63] printing some derogatory comments aimed at Forster and Oughtred in his Foreword. Forster, who dedicatedThe Circles of Proportion to the famous intellectual SirKenelm Digby, observed that another person had hastily anticipated Oughtred's publication.[64] It was left to Oughtred himself to publish hisJust Apologie explaining the priority of his inventions and writings, and showing the behaviour of Delamaine.[63][66][67]
It is stated in Cajori's book that John Napier was the first person to use to the decimal point and comma, butBartholomaeus Pitiscus was really the first to do so.[68]
Trigonometria, Hoc est, Modus Computandi Triangulorum Latera & Angulos was a collection compiled from Oughtred's papers by Richard Stokes and Arthur Haughton.[69] It contains about 36 pages of writing. Here the abbreviations for thetrigonometric functions are explained in further detail consisting of mathematical tables.[8] It carries a frontispiece portrait of Oughtred similar to that by Wenceslas Hollar, but re-engraved byWilliam Faithorne, and depicted as aged 83, and with a short epigram by "R.S." beneath. Longer verses addressed to Oughtred are prefixed byChristopher Wase.
A miscellaneous collection of his hitherto unpublished mathematical papers (in Latin) was edited and published by his friend SirCharles Scarborough in 1677.[70][71] The treatises contained are on these subjects:
Oughtred's invention of the slide rule consisted of taking a single "rule", already known to Gunter, and simplifying the method of employing it. Gunter required the use of apair of dividers to lay off distances on his rule; Oughtred made the step of sliding two rules past each other to achieve the same ends.[72] His original design of some time in the 1620s was for acircular slide rule; but he was not the first into print with this idea, which was published by Delamain in 1630. The conventional design of a sliding middle section for a linear rule was an invention of the 1650s.[73]
At the age of 23, Oughtred invented thedouble horizontal sundial, now named the Oughtred type after him.[74] A short descriptionThe description and use of the double Horizontall Dyall (16 pp.) was added to a 1653 edition (in English translation) of the pioneer book onrecreational mathematics,Récréations Mathématiques (1624) by Hendrik van Etten, a pseudonym ofJean Leurechon.[75] The translation itself is no longer attributed to Oughtred, but (probably) to Francis Malthus.[76]
According to his contemporaries, Oughtred had interests inalchemy andastrology.[78] TheHermetic science remained a philosophical touchstone among many reputable scientists of his time, and his studentThomas Henshaw copied a Diary and "Practike" given to him by his teacher.[79] He was well-acquainted with the astrologerWilliam Lilly who, as noted above, helped to prevent his ejection from his living in 1646.
John Aubrey states that (despite their political differences)Sir Richard Onslow, son of Sir Edward, also defended Oughtred against ejection in 1646. He adds that Oughtred was an astrologer, and successful in the use ofnatal astrology, and used to say that he did not know why it should be effective, but believed that some "genius" or "spirit" assisted. According to Aubrey,Elias Ashmole possessed the original copy in Oughtred's handwriting of his rational division of the twelve houses of thezodiac. Oughtred penned an approving testimonial, dated 16 October 1659, to the foot of the English abstract ofThe Cabal of the Twelve Houses Astrological by "Morinus" (Jean-Baptiste Morin) whichGeorge Wharton inserted in hisAlmanac for 1659.[80]
Portrait bust of Elias Ashmole, 1656, by William Faithorne
Aubrey suggests that Oughtred was happy to allow the country people to believe that he was capable of conjuring. Aubrey himself had seen a copy ofChristopher Cattan's work onGeomancy[81] annotated by Oughtred.[82] He reported that Oughtred had toldBishop Ward and Elias Ashmole that he had received sudden intuitions or solutions to problems when standing in particular places, or leaning against a particular oak or ash tree, "as if infused by a divine genius", after having pondered those problems unsuccessfully for months or years.[83]
Oughtred was well-known toElias Ashmole, as Ashmole stated in a note to Lilly's autobiographical sketch: "This gentleman I was very well acquainted with, having lived at the house over-against his, at Aldbury in Surrey, three or four years. E.A."[36]
The biography of Ashmole in theBiographia Britannica (1747)[84] called forth the supposition that Oughtred was a participant in Ashmole's admission tofreemasonry in 1646.Friedrich Nicolai, in both sections of his Essay (on the Templar and Masonic Orders) of 1783, associated Oughtred, Lilly, Wharton and other Astrologers in the formation of the order of Free and Accepted Masons inWarrington and London.[85] The statement was reinforced through repetition byThomas De Quincey,[86] and elaborated byJean-Marie Ragon,[87] but was debunked inA.G. Mackey'sHistory of Freemasonry (1906).[88]
Ashmole noted that he paid a visit to "Mr. Oughtred, the famous mathematician", on 15 September 1654, about three weeks after the Astrologers' Feast of that year.[89]
"Came that renowned mathematician, Mr. Oughtred, to see me, I sending my coach to bring him toWotton, being now very aged. Among other discourse, he told me he thought water to be thephilosopher'sfirst matter, and that he was well persuaded of the possibility of theirelixir; he believed the sun to be a material fire, the moon a continent, as appears by the lateselenographers; he had strong apprehensions of some significant event to happen the following year, from the calculation of difference with thediluvian period; and added that it might possibly be to convert the Jews by our Saviour'svisible appearance, or to judge the world; and therefore, his word was,Parate in occursum;[90] he saidOriginal Sin was not met with in theGreek Fathers, yet he believed the thing; this was from some discourse onDr. Taylor's late book, which I had lent him."[91]
Oughtred's name is remembered in the Oughtred Society, a group formed in the United States in 1991 forcollectors of slide rules. It produces the twice-yearlyJournal of the Oughtred Society and holds meetings and auctions for its members.[92][93]
^abcd'Oughtred (William)', in P. Bayle, translated and revised by J.P. Bernard, T. Birch and J. Lockman,A General Dictionary, Historical and Critical, (James Bettenham, for G. Strachan and J. Clarke, London 1734/1739), Vol. VIII,pp. 77-86 (Google).
^F. Willmoth, 'Oughtred, William (bap. 1575, d. 1660)',Oxford Dictionary of National Biography (2004).
^Wallis, P.J. (1968). "William Oughtred's 'Circles of Proportion' and 'Trigonometries'".Transactions of the Cambridge Bibliographical Society.4 (5):372–382.JSTOR41154471.
^abF. Cajori,William Oughtred, a Great Seventeenth-Century Teacher of Mathematics (Open Court Publishing Company, Chicago 1916),pp. 12-14 (Internet Archive).
^'Funeral ode by William Outhred', Surrey History Centre,ref. 6729/7/129 (Discovery Catalogue).
^Church of England Clergy database, Liber Cleri detail,CCEd Record ID: 199392, from British Library Harleian MS 595.
^Church of England Clergy database, Episcopal Register of Thomas Bilson (Winchester), Appointment Record ("Owtred")CCEd Record ID: 59030.
^ODNB, and seeAubrey's Brief Lives, Ed. Oliver Lawson Dick (Ann Arbor, Michigan 1962), pp. 222–224.
^'William Oughtred', in F. Willmoth,Sir Jonas Moore: Practical Mathematics and Restoration Science (The Boydell Press, Woodbridge 1993), pp. 43-61,at p. 45 (Google).
^Christes-Guift Carell, daughter of William and Dorothy, was baptized at Godalming on 21 April 1588 (Register).
^William Oughtred (Owtred) junr was baptized at Shalford on 9 October 1608 (Register): the younger children were baptized at Albury.
^J.J. O'Connor and E.F. Robertson, "Biographies: William Oughtred", MacTutor History of Mathematics archive,Last Update, 2017 (University of St Andrews).
^William "Owtred" also witnessed the first codicil (8 November 1620) to the Will of George Austen of Shalford (P.C.C. 1621, Dale quire).
^W. Bruce Bannerman (ed.),The Visitations of the county of Surrey taken in the years 1530, 1572 and 1623, Harleian Society Vol. XLIII (1899),pp. 88–89 (Internet Archive).
^Cf. Will of John Machell, Gentleman of Wonersh (P.C.C. 1647, Fine quire); Will of Elizabeth Machell of Wonersh (P.C.C. 1650, Pembroke quire).
^E.W. Brayley, J. Britton and E.W Brayley jnr.,A Topographical History of Surrey (G. Willis, London 1850), vol. II,p. 49 (Google). John Aubrey,The Natural History and Antiquities of the County of Surrey, 5 vols (E. Curll, London 1718-19), III,at pp. 258-59 (Internet Archive), quotes Oughtred's original Latin for these remarks.
^Gerald is sometimes referred to as "Gerard", but the name derives from his mother's family of Fitzgerald, seated atHatchlands Park inEast Clandon.
^ab"Yelverton, Sir Henry. Opinion that simony was involved in the contract between William Oughtred and John Tichborne for presentation to the church of Compton in Surrey", Papers of the More family of Loseley Park, Surrey, 1488-1682 (bulk 1538-1630), Surrey History Centre,ref. Z/407/Lb.668.4 (Discovery Catalogue). View original document atFolger Shakespeare Library. See also "Interrogatories", S.H.C.ref. LM/1329/104, 107, 109, 670 (Surrey History Centre Archives Catalogue).
^Church of England Clergy database, Episcopal Register of Thomas Bilson (Winchester), Appointment Record,CCEd Record ID: 59103. The advowson was in the lord of the manor, who was Sir Edward.
^Church of England Clergy database, Episcopal Register of Thomas Bilson (Winchester), Vacancy Evidence Record ("Outhred"),CCEd Record ID: 59115
^This was just one year after the ordination of John Donne (23 January 1615) and 6 months before his institution as rector of Sevenoaks (12 July 1616). The Clergy database, CCEd Ordination recordID 119823, and Appointment Evidence RecordID 114560.
^J. and J.A. Venn,Alumni Cantabrigienses Part 1 Vol. III (Cambridge University Press 1924),p. 288 (Internet Archive) (appointment 1610).
^"Parishes: Albury", in H.E. Malden (ed.),A History of the County of Surrey, Volume 3 (V.C.H./HMSO, London 1911),pp. 72-77 (British History Online): "was rector from 1610 to 1660".
^ab'26 September 1651' and following, in M.A.E. Green (ed.),Calendar of the Proceedings of the Committee for Compounding, 1643-1660, Part 4: Cases, July 1650 to December 1653 (HMSO 1892),p. 2472 (Internet Archive). See also The National Archives (UK), Chancery,Duncumbe v Onslow (1651),ref. C 10/467/79 (Discovery Catalogue).
^J. Aubrey,The Natural History and Antiquities of the County of Surrey, 5 vols (E. Curll, London 1718-19), IV,at pp. 65-70 (Internet Archive).
^The British Museum, Print Collections. Hollar: "Alburgum in Comitatu Surriæ, vulgo Albury",ref. Q,6. 89 (The British Museum). See also a set of 6 Hollar views of Albury in Bonham's auction of Prints and Multiples, (2 May 2019, Knightsbridge, London)Lot 7 (Bonhams).
^'Parishes: Albury', in H.E. Malden (ed.),A History of the County of Surrey Vol. 3 (VCH, London 1911),pp. 72-77, at fn 15 ff. (British History Online).
^"Ambo-dexters", in the figurative meaning, i.e. their allegiances swayed according to their own advantage.
^abWilliam Lilly's History of his Life and Times, from the year 1602 to 1681 (Published London 1715), Reprint (Charles Baldwyn, London 1822),pp. 135-37 (Internet Archive).
^J. Evelyn,Numismata: A Disccourse of Medals, Ancient and Modern... To which is added, A Discourse concerning Physiognomy (Benjamin Tooke, London 1697),p. 341 (Google).
^"Parishes: Albury", in H.E. Malden (ed.),A History of the County of Surrey, Volume 3 (V.C.H./HMSO, London 1911),pp. 72-77 (British History Online, accessed 6 December 2018).
^(W. Oughtred),To the English gentrie, and all others studious of the mathematicks which shall bee readers hereof. The just apologie of Wil: Oughtred, against the slaunderous insimulations of Richard Delamain, in a pamphlet called Grammelogia, or the Mathematicall Ring, or Mirifica Logarithmorum Projectio Circularis (A. Mathewes, London ?1634). Full text atUmich/eebo. Extracts in F. Cajori (1915) (Further reading).
^'VII: W. Robinson to Oughtred', in S.J. Rigaud (ed.),Correspondence of Scientific Men of the Seventeenth Century, 2 vols (University Press, Oxford 1841), Ipp. 11-14 (Google).
^Letters II-XXXVI, in S.P. Rigaud and S.J. Rigaud (eds),Correspondence of Scientific Men of the Seventeenth Century, 2 vols (University Press, Oxford 1841), I,pp. 3-92 (Google).
^H.M. Pycior,Symbols, Impossible Numbers, and Geometric Entanglements: British Algebra Through the Commentaries on Newton's Universal Arithmetick (1997), p. 42.
^T.C. Barnard,Cromwellian Ireland: English Government and Reform in Ireland 1649–1660 (2000), p. 223.
^'Appendix. No. XXV. Newton to Hawes', in J. Edleston (ed.),Correspondence of Sir Isaac Newton and Professor Cotes, Including Letters of Other Eminent Men (John W. Parker, London/John Deighton, Cambridge 1850), pp. 279-92,at pp. 291-92 (Google).
^J. Wallis,Arithmetica Infinitorum, sive Nova Methodus Inquirendi in Curvisineorum Quadraturam (Typis Leon: Lichfield Academiae Typographi, Impensis Tho. Robinson, Oxford 1656),unpaginated front matter (Internet Archive).
^(Londini, apud Thomam Harperum, 1631): see full page-views atGoogle.
^F. Cajori, 'The cross X as a symbol for multiplication',Nature, Vol. XCIV (1914), Abstract,pp. 363-64 (journal's webpage).
^Helena Mary Pycior,Symbols, Impossible Numbers, and Geometric Entanglements: British Algebra Through the Commentaries on Newton's Universal Arithmetick (1997), p. 48.
^Bayle, 'Oughtred (William)',General Dictionary, VIII,p. 78, note col. a (Google).
^G.[W.] Oughtred,Clavis Mathematica Denuo Limata, sive potius Fabricata (Londini, Excudebat Thomas Harper, sumptibus Thome Whitakeri, apud quem venales sunt in Cœmiterio D. Pauli, 1648); Full page views atGoogle.
^The captions "Versus Septentrionem", "versus Meridiem", suggest the opposite orientation, but the river Thames (to the south) is clearly visible in the "Septentrio" scene.
^W. Oughtred, ed. W. Forster,The Circles of Proportion and the Horizontall Instrument. The former shewing the maner how to work proportions both simple and compound: and the ready and easy resolving of quæstions both in arithmetic, geometrie, & astronomie: and is newly increased with an additament for navigation. All which rules may also be wrought with the penne by arithmetic, and the canon of triangles. The latter teaching how to work most quæstions, which may be performed by the globe: and to delineat dialls upon any kind of plaine. Both invented, and the uses of both written in Latine by Mr. W. O. Translated into English and set forth for the publique benefit by William Forster First issue (Printed for Elias Allen maker of these and all other Mathematical Instruments and are to be sold at his shop over against St Clements church without Temple Bar, London 1632); Second issue (Printed by Augustine Mathewes, and are to bee sold by Nic: Bourne at the Royall Exchange, London 1633), full text atUmich/eebo.
^Ball, W. W. Rouse (1917). "Review of William Oughtred: a great Seventeenth-century Teacher of Mathematics".Science Progress (1916-1919).11 (44):694–695.JSTOR43426914.
^A.J. Turner, 'William Oughtred, Richard Delamain and the Horizontal Instrument in seventeenth-century England',Annali dell'Istituto e Museo di storia della scienza di Firenze vol. 6 pt. 2 (1981), pp. 99-125.
^abc(W. Oughtred),To the English gentrie, and all others studious of the mathematicks which shall bee readers hereof. The Just Apologie of Wil: Oughtred, against the slaunderous insimulations of Richard Delamain, in a pamphlet called Grammelogia, or The Mathematicall Ring, or Mirifica Logarithmorum Projectio Circularis (A. Mathewes, London ?1634). Full text atUmich/eebo.
^abcd"To the Honourable and Renowned for vertue, learning, and true valour, Sir Kenelme Digbye, Knight (dated 1632)", in W. Oughtred, ed. W. Forster,The Circles of Proportion and the Horizontall Instrvment (1632, second issue 1633),unpaginated front matter; alsohere (Umich/eebo).
^R. Delamaine, ''Grammelogia, or, The mathematicall ring extracted from the logarythmes, and projected circular (printed 1631), full text atUmich/eebo: R. Delamaine,The Making, Description, and Use of a small portable Instrument called a Horizontall Quadrant (London: Printed [by Thomas Cotes] for Richard Hawkins and are to be sold at his shop in Chancery lane neere Sarjants Inne, 1632), full text atUmich/eebo.
^F.J. Swetz, 'Mathematical Treasure: Oughtred's Defense of His Slide Rule',Convergence (Online Periodical of the Mathematical Association of America),August 2018 (MAA).
^For a recent account more sympathetic to Delamaine, see V. Keller,The Interlopers: Early Stuart Projects and the Undisciplining of Knowledge (Johns Hopkins University Press, 2023),at pp. 230-32 (Google).
^L.C. Karpinsky, 'Review:William Oughtred, a Great Seventeenth-Century Teacher of Mathematics, by F. Cajori',The American Mathematical Monthly, Vol. 24 part 1 (January 1917),pp. 29-30 (jstor, open pdf). Cajori is also chastised for his having mis-spelled the name ofErasmus O. Schreckenfuchs.
^W. Oughtred, ed. R. Stokes and A. Haughton,Trigonometria, Hoc est, Modus Computandi Triangulorum Latera & Angulos Ex Canone Mathematico traditus et demonstratus... Una cum Tabulis Sinuum, Tangent & Secant, &c. (Londini, Typis R. & L.W. Leybourn, Impensis Thomæ Johnson, apud quem væneunt sub signo Clavis Aureæ in Cœmiterio S. Pauli, 1657); full page views atInternet Archive.
^'William Oughtred', in O. Manning and Bray,The History and Antiquities of the County of Surrey (John White/John Nichols and Son, London 1804-14), II,pp. 132-33 (Google).
^W. Oughtred, ed. C. Scarborough,Gulielmi Oughtredi Ætonensis, quondam Collegii Regalis Cantabrigia Socii, Opuscula Mathematica hactenus inedita (E Theatro Sheldoniano, Oxford 1677); Full pageviews atGoogle.
^W. Oughtred, 'The Description, and use of the double Horizontall Diall', in H. van Etten,Mathematicall recreations. Or, A collection of many problemes, extracted out of the ancient and modern philosophers (William Leake, London 1653),unnumbered pages, full text at Umich/eebo.
^Keith Thomas,Religion and the Decline of Magic (1973), p. 322 and 452n.
^D.R. Dickson, 'Thomas Henshaw and Sir Robert Paston's pursuit of the Red Elixir: an early collaboration between Fellows of the Royal Society',Notes and Records of the Royal Society of London, Vol. 51, No. 1 (Jan. 1997), pp. 57-76, at pp. 67-72.
^'The Cabal of the Twelve Houses Astrological', collected in J. Gadbury (ed.),The Works of that Late Most Excellent Philosopher and Astronomer, Sir George Wharton, bar. collected into one volume (M.H. for John Leigh, London 1683), pp. 189-208,at p. 208 (Google).
^La Geomance du Seigneur Christofe de Cattan, Gentilhomme Genevoys. Livre non moins plaisant et recreatif. Avec la roüe de Pythagoras (Gilles Gilles, Paris 1558). Full text (page views) atInternet Archive.
^Oughtred may have possessed the English translation by Francis Sparry,The Geomancie of Maister Christopher Catton, a Booke no lesse pleasant and recreative, then of a wittie invention (London 1591).
^'William Oughtred, 1575-1660', in R. Barber (ed.),John Aubrey - Brief Lives: A selection based upon existing contemporary portraits (Folio Society, London 1975), 232-37.
^C.F. Nicolai,Versuch über die Beschuldigungen welche dem Tempelherrenorden gemacht worden, und über dessen Geheimniß: Nebst einem Anhange über das Entstehen der Freymaurergesellschaft (Nicolai, Berlin und Stettin 1782), Theil I,at p. 188; Theil II,pp. 191-196 (Google).
^T. De Quincey, 'Historico-Critical Inquiry into the Origins of the Rosicrucians and the Free-Masons', in D. Masson (ed.),The Collected Writings of Thomas De Quincey, New and Enlarged Edition, Vol. XIII: Tales and Prose Phantasies (Adam and Charles Black, Edinburgh 1890),at pp. 425-26 (Google).
^J.M. Ragon,Orthodoxie maçonnique: suivie de la Maçonnerie occulte et de l'initiation hermétique (E. Dentu, Paris 1853),pp. 28-33,pp. 99-108, andpassim (Google).
^A.G. Mackey,The History of Freemasonry, 2 volumes (The Masonic History Company, New York and London 1906), II,pp. 306, 316-18 (Internet Archive).
^'The Life of Elias Ashmole, Esq.', inThe Lives of Those Eminent Antiquaries Elias Ashmole, Esquire, and Mr William Lilly, Written by Themselves (T. Davies, London 1774),at p. 321 (Google).
^I.e. "Praeparare in occursum Dei tui, Israel" (Book of Amos, Chapter IV, v. 12): "Prepare to meet thy God, O Israel".
^'Entry for 28 August 1655', in W. Bray (ed.),The Diary of John Evelyn, with a Biographical introduction by the editor, and a special introduction by Richard Garnett, LL.D., 2 vols (M. Walter Dunne, New York and London 1901), I,pp. 305-06 (Internet Archive, Retrieved 5 December 2018).