The Equatorie of the Planetis

Last updated

The Equatorie of the Planetis is a 14th-century scientific work which describes the construction and use of an equatorium. It was first studied in the early 1950s by Derek J. Price, and was formerly attributed to Geoffrey Chaucer. However, in 2014 it was shown to be written in the hand of the St Albans monk John Westwyk. It is largely written in Middle English, with some additions in Latin. It is accompanied by extensive astronomical tables, with Latin headings and annotations.

Contents

Manuscript

Peterhouse MS 75 was a composite manuscript. In the early 1950s, after Price discovered the Equatorie in it, the manuscript was split into two parts (and both parts rebound): MS 75.I, containing the Equatorie, and MS 75.II, containing works by Nicholas Trivet and Vegetius. [1]

MS 75.I has two parts: fol. 1r-71r contains largely astronomical tables, and some astrological material, in two hands; 71v-78v contains the text of the Equatorie treatise. [2] The parchment is of varying quality, with ten quires of pages measuring 365x260mm (except for the last quires). The ink is brown; there are signs of dampness on the upper edge, especially in the first quire, with some blurring in the fourth quire on the top of the pages. According to Rand Schmidt, the dampness and the wear and tear on some of the quires is evidence that the quires spent some time unbound. [3]

The text contains references to 31 December 1392, and this is used as a baseline date for many of the tables. John North showed that the text was written during the first nine months of 1393. [4] How it came to Peterhouse is not known, but it probably happened during the 15th century; around 1538 it is entered in Peterhouse catalog, as Tab. aequ. planetarum autore Simon Bredon. [5] The Equatorie occupies eight leaves of the manuscript; the phrase Radix chaucer appears on fol. 5v. [2]

The manuscript has been digitised for the Cambridge University Digital Library website, together with a virtual model of the equatorium. [6]

"Radix chaucer"

On f. 5v, in a note on a page full of tables, the manuscript has the number "1392", followed by that number in sexagesimal notation, and the text "deffea xpi & Rxa chaucer". Price, and following him other scholars, expanded this as "differentia Christi et radix Chaucer"—or "the difference (in number of days) between (the year of Christ) and the (year of the) radix of Chaucer"—the radix in question then being the year 1392. [1] F.N. Robinson was not convinced that this (third-person) reference indicated Chaucer's authorship. [7] However, John North argued that the attachment of a name to a relatively "trivial" piece of data made it likely that this was a case of self-citation. [8]

Discovery and authorship

The manuscript was in the library of Peterhouse, Cambridge by 1538, and probably by 1472. [2] [5] It was discovered there by the historian Derek de Solla Price in December 1951. [9] Although the 19th-century manuscript catalogue stated that the manuscript contained "directions for making an astrolabe (?)", Price identified the instrument as a planetary equatorium. [10] [11] He argued that the manuscript was authored by, and written in the hand of, Geoffrey Chaucer. [12] This was a controversial claim, and was treated with some scepticism by Chaucer scholars, [13] though it received influential backing from the historian of astronomy John North. [14] The manuscript was shown to be in the hand of John Westwyk by Kari Anne Rand in 2014. [15] [16] Further evidence for Westwyk's authorship was revealed by Seb Falk in a book published in 2020. [17]

Debate

Price published an abstract in 1953, [18] and the whole text (facsimile, transcription, and studies of the manuscript) in 1955. [19] He maintained the possibility that Chaucer authored the Equatorie, possibly as the missing part of his A Treatise on the Astrolabe , which describes the astrolabe; the Equatorie makes direct reference to it. [20] He argued that the manuscript was a holograph draft, written in the hand of its author, as shown by the many additions and corrections in the manuscript. [21]

Price offered five points as indicators of Chaucer's authorship: [19]

  1. Style and scientific treatment of the material are similar to A Treatise on the Astrolabe ;
  2. The text mentions that the year 1392 is the "Radix" (or "root") of Chaucer;
  3. The main hand (including that of the "Radix" note) resembled, Price thought, a document likely written in Chaucer's hand;
  4. Linguistic similarities between the Equatorie and Chaucer's work, including "verbal echoes of the Astrolabe;
  5. The author is influenced by Merton's school of astronomy but lives in London, and the writing is that of an amateur, not a professional astronomer; in addition, the writer is familiar with "the diplomatic cipher methods of his time"—all elements that correspond with Chaucer's biography.

Following the publication of the facsimile and transcription, G. Herdan published an article in which he concluded, based upon the percentage of words in the Equatorie of "Romance vocabulary" (which includes words from Old French, Anglo-Norman French, and Latin), that Chaucer was indeed the author: "The agreement between observation and expectation, or between fact and theory, is so striking that without going further into the question of statistical significance we may conclude that by the token of Romance vocabulary the Equatorie is to be regarded as a work by Chaucer". [22]

However, Price's arguments were challenged in various ways. His claim that the manuscript was a draft in the hand of its author was disputed, [13] though ultimately the evidence does seem to support it. [23] More significantly, Price's claim that the handwriting was that of Geoffrey Chaucer was disproved by analysis by Kari Anne Rand Schmidt. [24]

In 2014 Kari Anne Rand identified the hand as belonging to John Westwyk. [15] [16]

Content

Steps in the use of the Equatorie to find the position of a superior planet Equatorie workings.jpg
Steps in the use of the Equatorie to find the position of a superior planet

The text describes the construction of an equatorium, an instrument comparable to the astrolabe – but where an astrolabe shows the positions of the stars, an equatorium computes them for the planets, according to the Geocentric model of Ptolemy. [25] The instrument is constructed from two discs, six feet in diameter. One of them is solid, and is marked with characteristics of the orbits of the various planets: their apogee, their equants, and other centres. The other disc consists of "a ring, a diametral bar, and a rule pivoted at the centre of the bar". The two discs are joined and simulate the motions of each of the planets. A divided circle around the rims of the two discs allow for the transferral of information from sets of tables (the Alfonsine tables, from a Parisian document) that contain the data for each planet. [19]

The design was based on earlier equatoria, but refined for greater ease of manufacture and use. [26] It permits the user to find the longitudes of any classical planet (including the Sun and Moon, as well as the lunar latitude). [6]

Cipher

A cipher is used for some comments on the tables, and Price gave the key. He could not, however, discern what the rationale of or the ordering behind the key was – whether it was perhaps based on some medieval version of the Greek alphabet, or whether there was "some key-phrase or sentence such as a name or family motto" behind it. [27]

Related Research Articles

<i>The Canterbury Tales</i> Story collection by Geoffrey Chaucer

The Canterbury Tales is a collection of twenty-four stories that runs to over 17,000 lines written in Middle English by Geoffrey Chaucer between 1387 and 1400. It is widely regarded as Chaucer's magnum opus. The tales are presented as part of a story-telling contest by a group of pilgrims as they travel together from London to Canterbury to visit the shrine of Saint Thomas Becket at Canterbury Cathedral. The prize for this contest is a free meal at the Tabard Inn at Southwark on their return.

<span class="mw-page-title-main">Geoffrey Chaucer</span> English poet and author (c. 1340s – 1400)

Geoffrey Chaucer was an English poet, author, and civil servant best known for The Canterbury Tales. He has been called the "father of English literature", or, alternatively, the "father of English poetry". He was the first writer to be buried in what has since come to be called Poets' Corner, in Westminster Abbey. Chaucer also gained fame as a philosopher and astronomer, composing the scientific A Treatise on the Astrolabe for his 10-year-old son Lewis. He maintained a career in the civil service as a bureaucrat, courtier, diplomat, and member of parliament.

Bernardus Silvestris, also known as Bernard Silvestris and Bernard Silvester, was a medieval Platonist philosopher and poet of the 12th century.

<i>The Romaunt of the Rose</i> First English translation of "Le Roman de la rose" By Geoffrey Chaucer

The Romaunt of the Rose is a partial translation into Middle English of the French allegorical poem, Le Roman de la Rose. Originally believed to be the work of Chaucer, the Romaunt inspired controversy among 19th-century scholars when parts of the text were found to differ in style from Chaucer's other works. Also the text was found to contain three distinct fragments of translation. Together, the fragments—A, B, and C—provide a translation of approximately one-third of Le Roman.

<span class="mw-page-title-main">Gawain Poet</span> Unknown medieval poet

The "Gawain Poet", or less commonly the "Pearl Poet", is the name given to the author of Sir Gawain and the Green Knight, an alliterative poem written in 14th-century Middle English. Its author appears also to have written the poems Pearl, Patience, and Cleanness; some scholars suggest the author may also have composed Saint Erkenwald. Save for the last, all these works are known from a single surviving manuscript, the British Library holding 'Cotton MS' Nero A.x. This body of work includes some of the most highly-regarded poetry written in Middle English.

The Hengwrt Chaucer manuscript is an early-15th-century manuscript of the Canterbury Tales, held in the National Library of Wales, in Aberystwyth. It is an important source for Chaucer's text, and was possibly written by someone with access to an original authorial holograph, now lost.

<span class="mw-page-title-main">Derek J. de Solla Price</span> Physicist and science historian (1922–1983)

Derek John de Solla Price was a British physicist, historian of science, and information scientist. He was known for his investigation of the Antikythera mechanism, an ancient Greek planetary computer, and for quantitative studies on scientific publications, which led to his being described as the "Herald of scientometrics".

<i>A Treatise on the Astrolabe</i> Medieval instruction manual on the astrolabe by Geoffrey Chaucer

A Treatise on the Astrolabe is a medieval instruction manual on the astrolabe by Geoffrey Chaucer. It was completed in 1391. It describes both the form and the proper use of the instrument, and stands out as a prose technical work from a writer better known for poetry, written in English rather than the more typical Latin.

<span class="mw-page-title-main">Mashallah ibn Athari</span> 8/9th century Persian Jewish astrologer and astronomer

Māshāʾallāh ibn Atharī, known as Mashallah, was an 8th century Persian Jewish astrologer, astronomer, and mathematician. Originally from Khorasan, he lived in Basra during the reigns of the Abbasid caliphs al-Manṣūr and al-Ma’mūn, and was among those who introduced astrology and astronomy to Baghdad. The bibliographer ibn al-Nadim described Mashallah "as virtuous and in his time a leader in the science of jurisprudence, i.e. the science of judgments of the stars". Mashallah served as a court astrologer for the Abbasid caliphate and wrote works on astrology in Arabic. Some Latin translations survive.

<span class="mw-page-title-main">Schuttern Gospels</span>

The Schuttern Gospels is an early 9th century illuminated Gospel Book that was produced at Schuttern Abbey in Baden. According to a colophon on folio 206v, the manuscript was written by the deacon Liutharius, at the order of his abbot, Bertricus.

<span class="mw-page-title-main">Equatorium</span> Astronomical calculating instrument

An equatorium is an astronomical calculating instrument. It can be used for finding the positions of the Moon, Sun, and planets without arithmetic operations, using a geometrical model to represent the position of a given celestial body.

Simon Bredon was an English astronomer, mathematician, and physician and priest. He was a member of the Merton School, Oxford, elected a Fellow of Merton c. 1330, perhaps until the year 1342, having formerly been a member of Balliol. He was a Doctor of Medicine of the University of Oxford. He left manuscripts and scientific instruments to a number of Oxford colleges, perhaps including the bequest of the Oriel astrolabe, which is now in the Museum of the History of Science.

Nicholas of Lynn or Lynne, also known in Latin as Nicolas de Linna, was an English astronomer of the 14th century.

The Trinity Gower D Scribe, often referred to simply as Scribe D, was a professional scribe and copyist of literary manuscripts active during the late fourteenth and early fifteenth century in London, England. Although his real name long remained unknown, Scribe D has been described as "so well known to students of late Middle English manuscripts that he hardly needs any introduction".

The Lincoln Thornton Manuscript is a medieval manuscript compiled and copied by the fifteenth-century English scribe and landowner Robert Thornton, MS 91 in the library of Lincoln Cathedral. The manuscript is notable for containing single versions of important poems such as the Alliterative Morte Arthure and Sir Perceval of Galles, and gives evidence of the variegated literary culture of fifteenth-century England. The manuscript contains three main sections: the first one contains mainly narrative poems ; the second contains mainly religious poems and includes texts by Richard Rolle, giving evidence of works by that author which are now lost; and the third section contains a medical treatise, the Liber de diversis medicinis.

<span class="mw-page-title-main">John Shirley (scribe)</span> English writer and scribe (c. 1366–1456)

John Shirley was an author, translator, and scribe. As a scribe of later Middle English literature, he is particularly known for transcribing works by John Lydgate and Geoffrey Chaucer.

John Westwyk was an English astronomer, adventurer, Benedictine monk, and author of the Equatorie of the Planetis.

Richard Middlewood Wilson was an English philologist.

Oxford, Bodleian Library, MS Fairfax 16, also known as the Fairfax Manuscript, is a fifteenth-century Middle English poetic anthology which contains one of the finest collections of Chaucerian verse of this period. Owned and commissioned by John Stanley of Hooton, Cheshire, Fairfax 16 was produced in Oxford or London in the mid-fifteenth century. Thomas Fairfax bequeathed it to the Bodleian Library in 1671.

<span class="mw-page-title-main">Pearl Manuscript</span> 14th century English decorated text in book

The Pearl Manuscript, also known as the Gawain manuscript, is an illuminated manuscript produced somewhere in northern England in the late 14th century or the beginning of the 15th century. It is one of the best-known Middle English manuscripts, the only one containing alliterative verse solely, and the oldest surviving English manuscript to have full-page illustrations. It contains the only surviving copies of four of the masterpieces of medieval English literature: Sir Gawain and the Green Knight, Pearl, Cleanness, and Patience. It has been described as "one of the greatest manuscript treasures for medieval literature", and "the most famous of all romance manuscripts".

References

Notes

  1. 1 2 Rand Schmidt 1993, p. 103.
  2. 1 2 3 Cambridge, Peterhouse MS 75.I
  3. Rand Schmidt 1993, p. 103-5.
  4. North 1988, p. 171.
  5. 1 2 Rand Schmidt 1993, p. 112-3.
  6. 1 2 "Equatorie of the Planetis (MS Peterhouse 75.I)". University of Cambridge Digital Library. Archived from the original on 9 January 2021. Retrieved 8 March 2021.
  7. Rand Schmidt 1993, p. 8-9.
  8. North 1988, p. 174.
  9. Falk, Seb (2014). "The scholar as craftsman: Derek de Solla Price and the reconstruction of a medieval instrument". Notes and Records of the Royal Society. 68 (2): 111–134. doi: 10.1098/rsnr.2013.0062 . PMC   4006160 . PMID   24921105.
  10. James, M.R. (1899). A descriptive catalogue of the manuscripts in the library of Peterhouse. Cambridge: Cambridge University Press. p. 94.
  11. Price 1975, p. 26.
  12. Price 1955, p. 3.
  13. 1 2 Edwards, A.S.G.; Mooney, Linne R. (1991). "Is the "Equatorie of the Planets" a Chaucer Holograph?". The Chaucer Review. 26 (1): 31–42. JSTOR   25094179.
  14. North 1988, p. 169-77.
  15. 1 2 Bridge, Mark (18 June 2020). "'Forgotten' monk paved the way for Copernicus". The Times. Retrieved 24 September 2020.
  16. 1 2 Rand 2015.
  17. Falk 2020.
  18. Price, Derek J. (1953). "The Equatorie of the Planetis (Abstract)". Bulletin of the British Society for the History of Science . 1 (9): 223–26. doi: 10.1017/S095056360000083X . JSTOR   4024774.
  19. 1 2 3 Price 1955.
  20. Falk 2020, p. 261.
  21. Price 1955, p. 143-5.
  22. Herdan, G. (1956). "Chaucer's Authorship of the Equatorie of the Planetis: The Use of Romance Vocabulary as Evidence". Language . 32 (2): 254–259. doi:10.2307/411002. JSTOR   411002.
  23. Rand Schmidt 1993, p. 15-22.
  24. Rand Schmidt 1993, p. 28-39.
  25. "What's the difference between an astrolabe and an equatorium?". sebfalk.com. Archived from the original on 23 October 2020. Retrieved 8 March 2021.
  26. Falk 2020, p. 272-9.
  27. Price 1955, p. 182-7.

Bibliography