Background

Francis Bailey was born at Newbury in Berkshire, on the 28th of April, 1774. He was the third son in the family of Richard Baily, a banker.

Education

Baily received only an elementary education.

Career

At the age of fourteen Baily was apprenticed to a London mercantile firm. As soon as his seven years of apprenticeship were up, Baily set sail for the United States and two years of rugged adventures at sea and in the backwoods, which he described in his Journal. He returned to England in 1798, hoping to spend his life as an explorer. When all efforts to obtain backing for such a career proved fruitless, he became a stockbroker instead. Before the end of the Napoleonic wars, he had published several actuarial tables, An Epitome of Universal History, and an astronomical paper (1811).

Having prospered on the stock exchange, Baily retired at the age of fifty to devote his full time to astronomy. He had become a fellow of the Royal Society in 1821 and was to serve the Astronomical Society as president during four two-year terms, the first beginning in 1825 and the last interrupted by his death.

Baily’s first substantial astronomical work dealt with methods of determining latitude and time by the stars. Since no up-to-date star catalog was available for this purpose, Baily calculated the mean positions of 2,881 stars for the epoch 1 January 1830; this work, published in 1826, earned him his first Gold Medal from the Astronomical Society. (The second came in 1843, for his redetermination of the density of the earth.)

Work on the standard pendulum, the standard yard, and the ellipticity of the earth followed, interspersed among revisions of many star catalogs. In the course of preparing a new edition of the Histórica coelestis of 1712, Baily found and published (1835) evidence that Edmund Hailey, the second astronomer royal, had unduly maligned his predecessor, John Flamsteed.

It was during the annular eclipse of 15 May 1836, which he observed from Inch Bonney in Scotland, that Baily first saw the “beads.” They are a transient phenomenon often seen at the beginning and end of totality in a solar eclipse when the edge of the moon is close to inner tangency and a thin crescent of sunlight shines between mountains on the moon’s limb. In Baily’s own words, they appear as “a row of lucid points, like a string of bright beads running along with the lunar disc with beautiful coruscations of light.” His report (1838) included a list of all previous observers, beginning with Halley in 1715, and aroused keen interest. For the solar eclipse of 8 July 1842, many astronomers accordingly journeyed to Italy, where the eclipse was to be total. The British astronomer royal, George B. Airy, who was in Turin, looked for, but did not see, “Mr. Baily’s beads”; Baily himself, in Pavia, did see them but only at the beginning of totality (1846).

Baily died in London on 30 August 1844 and was buried in the family vault in St Mary's Church in Thatcham.

Achievements

• Baily's main achievement was in being one of the founders of the Astronomical Society of London (later the Royal Astronomical Society). His enthusiasm and organizing ability served to arouse interest in astronomy and to put its practical aspects on a firm footing. Today he is remembered (although frequently with his name misspelled) for “Baily’s beads,” an effect seen during solar eclipses by many men before Baily but never so vividly described.
  
  Baily was awarded the Gold Medal of the Royal Astronomical Society in 1827, for his preparation of the Astronomical Society's Catalogue of 2881 stars. The lunar crater Baily was named in his honor, as was the rigid and thermally insensitive alloy used to cast the 1855 standard yard (Baily's metal, 16 parts copper, 2.5 parts tin, 1 part zinc), as well as a local primary school in his home town of Thatcham (Francis Baily Primary School).

Works

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  • An Account of the Revd. John Flamsteed, the First Astronomer-Royal: To Which Is Added, his British Catalogue of Stars, Corrected and Enlarged

    (Francis Baily (1774-1844), a stockbroker who became Presi...)

  • Memoir on a new and certain method of ascertaining the figure of the earth by means of occultations
  • Astronomische Nachrichten 1868
  • A Catalogue of 9766 Stars in the Southern Hemisphere, for the Beginning of the Year 1750, from the Observations of the Abbe de Lacaille Made at the Cape of Good Hope in the Years 1751 and 1752 1826
  • An Address To Astronomical Observers, Relative To The Improvement And Extension Of The Astronomical Society's Catalogue Of 2881 Principal Stars by F. Baily.
  • Journal of a Tour in Unsettled Parts of North America in 1796 & 1797 1797
  • Astronomical Tables and Formulæ Together with a Variety of Problems Explanatory of Their Use and Application: To Which Are Prefixed the Elements of the Solar System
  • Supplement to the Account of the Revd. John Flamsteed, the First Astronomer-Royal

Membership

Francis Baily was a member of the Royal Astronomical Society from 1821.

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  the Royal Astronomical Society (RAS) , United Kingdom

  1821 - 1844

Connections

Father:

Richard Baily

References

• The Biographical Encyclopedia of Astronomers The Biographical Encyclopedia of Astronomers is a unique and valuable resource for historians and astronomers alike. The two volumes include approximately 1550 biographical sketches on astronomers from antiquity to modern times. It is the collective work of about 400 authors edited by an editorial board of 9 historians and astronomers, and provides additional details on the nature of an entry and some summary statistics on the content of entries.
  2009
• Dictionary of Scientific Biography
  1970