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Title: Cassini’s heliometer
Format: photograph: print
Date: 1695
Description: The church of San Petronio in Bologna was the site of a solar observatory as early as 1576 when Egnazio Danti, cosmographer to Cosimo I de’ Medici, installed the first meridian line there. Unfortunately it did not fulfill its purpose, which was to provide an accurate date for the spring equinox, thence Easter. In spite of uncertainties about the precise length of the solar year, the Gregorian calendar was promulgated anyway, in 1582. We still use it today. Almost 75 years later, the opportunity arose to reconstruct the meridian. Enter a 29-year-old astronomy professor named Giovanni Domenico Cassini. Cassini increased the height of Danti’s solar peephole—or gnomon hole—to 1000 inches (based on the French foot) or 27.07 meters above the church floor. The length of the meridian line was increased by x2.5 to 66.71 meters, or 1/600,000 of the Earth’s circumference, per Cassini’s calculation. The line had to run on the floor between the aisles and columns of the church on a north-south axis without obstruction. The instrument was tested with great fanfare at the summer solstice of 1655 and proved fully successful. Cassini’s illustrated account of his heliometer was published 40 years later in 1695 with the title La Meridiana del tempio di S. Petronio. The image shown here is taken from a large foldout plate depicting the design and details of installation.

Title: Antoni van Leeuwenhoek (1632-1723)
Format: photograph: negative
Date: 1684
Description: Portrait from volume two of his four-volume Werken, published in 1689. Leeuwenhoek was the son of a middle-class shopkeeper in Delft, Netherlands. He began his professional life as a cloth merchant and then served in several civil service posts in Delft. As the Court Surveyor of Holland, he acquired an interest in lens grinding and fashioned his first microscope in 1671. He communicated his observations to other scientific practitioners in letters written in Dutch that were later collected together and published in four volumes

Title: Hand-painted illustration from the autograph album of Johann Jakob Frisch
Format: photograph: negative
Date: 1624
Description: Frisch was a nephew of Johannes Kepler. The album was kept by Frisch while a law student at the University of Tubingen (from 1624 to 1631), where Kepler himself also had studied. Autograph entries are typicaly in Latin, and range from a few lines of verse or prose to elaborate miniature illustrations, comic and serious. Kepler’s autograph is included in the book within a Latin inscription dated 1625.

Title: Hevelius and wife--illustration
Format: photograph: negative
Date: 1673
Description: Hevelius and wife observing at sextant from Hevelius’ “Machinae Coelestis Pars Prior.” (1673).

Title: Galileo, table of observations of the Medicean Planets, from Istoria e Dimostrazioni intorno alle Macchie Solari (History and Demonstration concerning Sunspots), Rome, 1613
Format: photograph: print
Date: 1613
Description: The Medicean Planets was the name given to the moons of Jupiter which Galileo discovered with his telescope in 1610. This table of observations was made during the months of April and March, 1613, and is a daily record of the positions of the moons relative to Jupiter.

Title: Fleet Prison
Format: photograph: negative
Date: 1808
Description: Ackermann, R., The Microcosm of London, Vol. II, London 1809 Plate no. 36

Title: Water Engine, Cold-Bath-Field’s Prison
Format: photograph: negative
Date: 1808
Description: Ackermann, R., The Microcosm of London, Vol. I, London 1808 Plate no. 19

Title: Oculus Enoch et Eliae, sive Radius Sideromysticus pars Prima
Format: photograph: negative
Date: 1645
Description: Anton Maria Schyrleus (1597-1660) was a Capuchin priest and professor, who worked in Bohemia, Trier and Ravenna. His astronomical work was completed in the low countries in the 1640s, and resulted in this rather unusual work -- a richly illustrated example of baroque natural philosophy. The Oculus might be considered a mystical work, reflecting the harmonies of an earth-centered, Tychonic cosmos in scriptural terms. The illustrations give a vivid impression of its combination of technical astronomy and mechanics with rich symbolism.

Title: Oculus Enoch et Eliae, sive Radius Sideromysticus pars Prima
Format: photograph: negative
Date: 1645
Description: Anton Maria Schyrleus (1597-1660) was a Capuchin priest and professor, who worked in Bohemia, Trier and Ravenna. His astronomical work was completed in the low countries in the 1640s, and resulted in this rather unusual work -- a richly illustrated example of baroque natural philosophy. The Oculus might be considered a mystical work, reflecting the harmonies of an earth-centered, Tychonic cosmos in scriptural terms. The illustrations give a vivid impression of its combination of technical astronomy and mechanics with rich symbolism.

Title: New Covent Garden Theatre
Format: photograph: negative
Date: 1810
Description: Ackermann, R., The Microcosm of London, Vol. III, London 1809-1810 Plate no. 100

Title: “Mr. Fezziwig’s Ball”--Dickens
Format: photograph: negative

Title: Diagram of the human hand, from Giordano Bruno’s discussion of the properties of the number 5 in De monade numero et figura.
Format: photograph: print
Date: 1591
Description: De monade numero et figura (On the Monad, Number and Figure) is part of the trilogy of Latin verse works published in Frankfurt in 1591 and considered to be Bruno’s philosophical testament. In the De monade Bruno discusses Pythagorean number symbolism and the meanings of the numbers 1 to 10.

Title: Oculus Enoch et Eliae, sive Radius Sideromysticus pars Prima
Format: photograph: negative
Date: 1645
Description: Anton Maria Schyrleus (1597-1660) was a Capuchin priest and professor, who worked in Bohemia, Trier and Ravenna. His astronomical work was completed in the low countries in the 1640s, and resulted in this rather unusual work -- a richly illustrated example of baroque natural philosophy. The Oculus might be considered a mystical work, reflecting the harmonies of an earth-centered, Tychonic cosmos in scriptural terms. The illustrations give a vivid impression of its combination of technical astronomy and mechanics with rich symbolism.

Title: J.T Desaguliers - plate 31 from A Course of Experimental Philosophy (London, 1734-44)
Format: photograph: negative
Description: Jean Theophilus Desaguliers, a protestant refugee from France, established himself as one of the most prominent advocates of the Newtonian philosophy in the first quarter of the eighteenth century. While trying to clarify some of the theoretical aspects of Newtonianism, he also became deeply concerned with the religious, social and political implications of Newton’s work: for example, at the accession of George II in 1727 Desaguliers published a panegyric entitled The Newtonian System of the World: the best Model of Government. The “planetarium” was Desaguliers’ device to model the motions of the planets. It was three feet in diameter. When the demonstrator turned the crank, all the spheres moved in proportion to the actual mean motions of the planets.

Title: Kepler - Table II, from Mysterium cosmographicum
Format: photograph: negative
Date: 1596

Title: “The Lecture”
Format: photograph: print
Description: William Hogarth, “The Lecture,” reprinted in “The Works of William Hogarth,” London.

Title: Portions of buckwheat plant
Format: photograph: negative
Date: 1684
Description: From Antoni van Leeuwenhoek’s Werken (vol. 2)

Title: Illustration of Torbern Bergman’s chemical apparatus from Opuscula Physica et Chemica.
Format: photograph: print
Date: 1784
Description: This translation from the original Latin is by Edmund Cullen. It includes notes and illustrations by Cullen and was published in 1784 by J. Murray, London.

Title: Galileo, portrait of three astronomers, frontispiece from Systema Cosmicum, Augustae Treboc. [Strasbourg], 1635
Format: photograph: negative
Date: 1635
Description: In the first Latin edition of the Dialogo, the portrait has been reengraved and significantly altered from the Italian original. Two columns have been added, and above them the curtain with the dedication to Galileo’s patron, the Grand Duke of Tuscany, is held not by Italian putti but by little angels, who also support the Medici crest. The astronomers’ poses are similar to the original, but Copernicus looks out toward the reader and holds his model of the heliocentric system in a more prominent position. The names of the astronomers are engraved in the ground rather than on their garments. The arrow points more clearly to Copernicus. The small stones on the ground, much more than in the Italian version, appear to represent the the configuration of sun and planets.

Title: Lambeth Palace
Format: photograph: negative
Date: 1808
Description: Ackermann, R., The Microcosm of London, Vol. II, London 1809 Plate no. 48