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Edmund Halley's Controversial Star Chart, Drawn From the Observations of John Flamsteed

Nice example of this important early 2 sheet chart of the Zodiac, first published by John Senex in London in 1718.

John Senex was one of the first English publishers to produce celestial charts. The Zodiacus Stellatus was drawn from the work of John Flamsteed, the Astronomer Royal, whose meticulous nature resulted in his refusal to publish his work in his lifetime. However, in 1712, under pressure from Isaac Newton and Edmond Halley, Flamsteed gave the Royal Society a manuscript copy of his catalogue of stars, along with explanatory text, authorizing publication of the text only. Ignoring Flamsteed, Halley published the Catalogue of Stars. Flamsteed attempted to buy and destroy every copy of the book he could find.  Next, Halley constructed this Zodiacus Stellatus, from Flamsteed's observations, which was published under Senex's name. In a letter from one of Flamsteed's assistants to another from 1720, Joseph Crosthwaite commented:

"... Senex is so much a tool of Dr. Halley's, and affronted Mr. Flamsteed so much in his lifetime by engraving the 'Zodiacus Stellatus', and putting his own name to it, in order to screen Dr. Halley from the law, that I am afraid he is not to be trusted."   One of Flamsteed's assistants, Joseph Crosthwaite, wrote in 1720

.. Senex is so much a tool of Dr. Halley's, and affronted Mr. Flamsteed so much in his lifetime by engraving the 'Zodiacus Stellatus', and putting his own name to it, in order to screen Dr. Halley from the law, that I am afraid he is not to be trusted." (quoted by Warner, 'The Sky Explored', p.242).

As noted by Kanas,

In part through his collaboration with Halley, Senex produced a number of celestial maps . . . which were quite popular with astronomers and navigators. . . One of these maps was originally published in 1718 and showed the zodiac constellations in three long strips arranged vertically over two pages on a map labeled Zodiacus Stellatus Fixas Omnes Hactenus Cognitas . . . Each strip was centered 8 degrees above and below the ecliptic using a cylindrical projection with geocentric orientation. . . Since the stars were derived from Halley's unauthorized edition of Flamsteed's catalog, [Flamsteed having refused to publish his work during his lifetime] . . . , the appearance of this and other maps by Senex created great consternation at Greenwich [where Flamsteed was the Royal Astronomer].

The work was first offered for sale in 1718, based upo two advertisements placed in the Post Boy  (issue 4477) for 5th-8th April, 1718 

This Day is publish'd

Zodiacus Stellatus fixas omnes hactenus cognitas, ad quas Lunæ appulsus ullibi terrarum Telescopio observari poterunt, complexus. Or, An exact Description of all the fix'd Stars, to which the Moon or Planets can at any time apply, carefully laid down on two large sheets, from the British Catalogue of Stars lately publish'd; being of use to all Lovers of Astronomy, and particularly to such as may be desirous to put in Practice the Art of finding the Longitude by Help of the Moon.

Senex's work would remain the only representation of the constellations of the Zodiac until Pierre Charles Le Monnier's work of 1755.

The map includes a fantastic description legend at the bottom, which begins as follows:

The DESCRIPTION and USE of the Starry ZODIAK. Finding that nothing would more conduce to encourage Persons to ye Study of Astronomy than to remove those difficulties which commonly deterr Beginners; and having by ye favour of a Person of Quality, procured a Copy of the Britannick Catalogue of Fixt Stars, I was persuaded ye I should do the Science a considerable piece of service, if I represented to a competent scale and in their true Situation and Magnitude, all those Starrs to which the Moon or Planetts can at any time make their Appulses. For by this means those that are provided with a Telescope only may be able to Judge of ye accuracy of our Astronomical Tables & Ephemerides; and by ye farther help of yes Micrometer & Pendulum Clock, may make such Observations as may be of use to compleat ye Theory of ye Celestial Motions; ye opportunitys of Observing being readily had by ye help of ye Zodiack.
The British Catalogue ye being adopted to ye beginning of ye year 1600, I was advised to follow it without reducing it to ye present Time; because it would always be necessary to allow for ye increase of ye Starrs Longitude in succeeding Years, and it is no more work to subtract 30 or 40 then 15 or 20; This reduction being easily made, by subtracting 15 min: for every 18 years lapsed since 1690, from ye place of ye Moon or Planet found in te Ephemerides, when you would compare them with ye Starrs places in the Zodiack.
That ye Planets might be transferrd with more certainty into it I have drawn ye lines drawing each Degree both of Longitude and Latitude into quarters sufficiently distinguished from ye entire Degrees by ye smallness of ye stroaks for which reason there will be no need to use Compasses. Our Scale being so large as to afford a 10th of an Inch to each quarter of a Degree. Thus for Example if you desire to see how ye 3 Superiour Planets are situated among ye fixt Starrs ye 12st of April 1718; We find by ye Ephemerides of Mr. G. Parker for which are computed from Astronomia Carolina with sufficient care ye Saturn . . .

John Senex produced a number of fine maps, celestial charts, sea charts and and globes at the beginning of the 18th Century. This fine chart was re-issued for over 50 years, all examples of which are rare on the market. Other publishers of later editions included John Bowles, Carrington Bowles and Robert Sayer.


We note only a single example (this copy) offered in a dealer catalogue in the past 30 years.  We also offered an example for sale in 2012 and 2017.

Warner, D.J. (Sky) Senex 2; Shirley, R.W. (BL Atlases) C.SEN-1a, #5,6. Kanas, Star Maps, pp. 205-206.
John Senex Biography

John Senex (1678-1740) was one of the foremost mapmakers in England in the early eighteenth century. He was also a surveyor, globemaker, and geographer. As a young man, he was apprenticed to Robert Clavell, a bookseller. He worked with several mapmakers over the course of his career, including Jeremiah Seller and Charles Price. In 1728, Senex was elected as a Fellow of the Royal Society, a rarity for mapmakers. The Fellowship reflects his career-long association as engraver to the Society and publisher of maps by Edmund Halley, among other luminaries. He is best known for his English Atlas (1714), which remained in print until the 1760s. After his death in 1740 his widow, Mary, carried on the business until 1755. Thereafter, his stock was acquired by William Herbert and Robert Sayer (maps) and James Ferguson (globes).