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Thomas Hood

The Use of the Celestial Globe in Plano, set forth in two Hemispheres.., Imprinted for Thobie Cooke at London, 1590

The Use of the Celestial Globe in Plano, set forth in two Hemispheres.., Imprinted for Thobie Cooke at London, 1590

Le due tavole, incise nel 1590 da Augustinus Ryther, sono invece presentate per cortesia di

VERY RARE, only early edition of this work on the use of celestial globes. The text is in the form of a dialogue between a Scholar and Master and was intended to aid the student astronomer/ cosmographer/ navigator to recognize the stars and their constellations. It contains a table of stars listing their longitude, latitude, magnitude and constellation. There is also a description of the nova that appeared in Cassiopeia in 1572-4. This event was witnessed across Europe and attracted the attention of the best astronomers of the day, among them Tycho Brahe, who published his account in 1575. This new star initially reached the brightness of Venus. Hood recounts the various theories regarding this phenomenon (that it was one of the stars of Cassiopeia or a comet) with much of the argument centering on whether this new light moved or not. By showing that it remained fixed, Brahe proved that it was not an atmospheric disturbance, such as a comet, but a new star. While Brahe himself was not a supporter of Copernicus’ theory, that the sun not the earth is at rest at the centre of the universe, his discoveries in relation to the nova made this theory easier to accept.

Hood (fl. 1582-1598), a graduate of Cambridge, held the first English lectureship in mathematics and was one of the first popularisers of the ‘new learning’. This appointment was initiated and financed in 1582 by Thomas Smith, to whom this work is dedicated, and the lectures were given in the city of London. Smith was the first Governor of the East India Company, Governor of the Muscovy Company and Treasurer of the Virginia Company and a patron of science, trade and exploration. Hood’s publications, which ranged from an English translation of Ramus’ ‘Elements of Geometrie’ to a guide for mariners, as well as his inventions of mathematical instruments, show the wide scope of mathematics as a discipline in the late C16. He also lectured on geography and navigation. He is credited with popularising astronomy and the Copernican theory in England. This is the first of his two works on the celestial globe; the second was published in 1592 (‘The use of both the Globes Celestiall and Terestriall’, London). In 1589 Hood was, with Hakluyt, one of the subscribers to Raleigh’s Virigina Company; he invented a sector, ancestor of the slide rule and the calculating machine in 1598, the same year as Galileo.

According to the present t-p, one could also buy from Mr Hood himself at his house in Abchurch Lane ‘two hemispheres’ ( 22 inch square) to use with the present text. They illustrate the various constellations and stars by human and animal figures. Regrettably however they were very rarely united with the book and where they have survived they have generally done so separately. ‘There is a copy in the British Museum, the text (without the plates) being in the Library, and coloured impressions of the two planispheres in the Map Department. This is the only copy noted in the STC. Bishop adds three further copies in America, i.e. Washington, New York P.L., and Charlotesville, and of these Charlottesville alone has any plate, and only the South Polar Region’ (Hind I, p.142).

STC 13697 (4 libs. + Kraus in US) ‘Tp has advt. for the sale of the hemispheres at the author’s house in Abchurch Lane. They are eng. by A. Ryther and lacking in most copies’. ESTC s118875. Hind I, p.139. Houzeau and Lancaster 2785. Taylor ‘Late Stuart and Early Tudor Geography’, 346. Not in Honeyman.

Le due tavole sono costruite in proiezione polare equidistante ed hanno come riferimento i due poli eclittici, sono in visione convessa. Le tavole si estendono fino all’eclittica che fa da perimetro ad entrambe, pertanto le costellazioni zodiacali appaiono tutte ed ognuna parzialmente rappresentate nei due planisferi. Curiosamente la Bilancia non sembra autonoma ed è disegnata sovrapposta alle chele dello Scorpione.

la Bilancia non sembra autonoma ed è disegnata sovrapposta alle chele dello Scorpione.

Vi appaiono le stelle suddivise in sei magnitudini, sono segnalate inoltre le nebulose e le oscure, la relativa scala Stellaru magnitudines sic expressimus è posta tra le costellazioni dell’Ursa Major e dell’Auriga. I nomi in diverse lingue delle stelle e delle costellazioni sono ampiamente elencati in didascalie poste a fianco dell’immagine mitologica. Il modello seguito dall’incisore Augustinus Ryther è quello utilizzato nel globo del Mercatore. Oltre alle costellazioni tolemaiche ritroviamo Antinous, Caput Medusae e la Chioma di Berenice , questa sotto il nome di Cincinnus. Hood è il primo cartografo a segnalare con un nome proprio il nastro che unisce i due Pesci zodiacali, Linum Septentrionale e Linum Australe, http://www.atlascoelestis.com/desu%20hood.htm.

Il reticolo eclittico è composto dai due poli, dall’eclittica che riporta una scala graduata al passo di un grado di longitudine, da cerchi di latitudine ogni 10° e da linee radiali ogni 30° di longitudine; su quella che congiunge i punti primaverile e autunnale degli equinozi è posta una scala graduata con tacche di un grado di latitudine, Gradus Latitidinis Stellarum.

Il reticolo equatoriale è rappresentato dalle porzioni di pertinenza dell’equatore, dai due poli, dai circoli polari artico ed antartico e dai tropici del Cancro e del Capricorno. Sulla linea che unisce il solstizio invernale con quello estivo è posta una scala graduata, Gradus Declinationis Stellarum, con il passo di un grado di declinazione.

Honoratissimo viro literaru amatissimo, Joanni Lumleyo. Equiti Domino Lumleyo dedicavit opus hoc Thomas Hood in Civitate Londinensi Praefector Mathematicus, quondam Collegii Sanctae atq. Individuce trinitatis in Academia Cantabrigiensi Socius.