Exhibit of the Month - November 2021
November 3 - 30, 2021 Ante-room to the General reading Room (gate A), open Monday to Saturday 9 am - 7 pm
Admission 10 CZK (free for the NL readers).
Tabulae Rudolphinae …traduxit Ioannes Keplerus – [Johannes Kepler, Rudolphine Tables]
Published in Ulm, 1627
NK CR, shelf mark 14 B 73 and 49 A 15
Johannes Kepler, whose 450th birth anniversary will be commemorated at the end of this year, is known particularly for his laws of planetary motion. He moved in Prague in 1600 to join Tycho Brahe. After a short collaboration ended with Tycho´s death, he became the Imperial Mathematician and Astronomer. He also undertook Tycho´s commitment to draw up astronomical tables for the Emperor. It took him almost three decades. The Tables were published in Ulm in 1627, achieving much higher accuracy than all previous tables and becaming an essential tool for astronomers, astrologers, sailors, surveyors and sundial mechanics.
The frontispiece illustration of the Tables depicts an allegorical Temple of muse of astronomy Urania, the columns of which are assigned to Kepler´s predecessors and feature their astronomical devices. As astronomy has developed since ancient times, also the columns have been structurally refined from behind. Far left, there is the column of Aratus with an armillary shpere, and in front of it that, of Hipparchus with a globe. Far right, there is the column of Meton with the symbol of the calendar Metonic cycle, and in front of it that of Ptolemy with an astrolabe. In front left, Nicolaus Copernicus is sitting at the Doric column adorned with a wooden triquetrum and Jacob´s staff. In front right, Tycho Brahe is standing at the Corinthian column with a quadrant and a sextant. Tycho is pointing to the ceiling of the Temple, where his system of the Universe is depicted and asks: Quid si sic? (What, if it is like so?). However, thanks to Kepler´s refinement of Copernicus´model, the answer should be: No.
On the roof of the temple, the goddeses are depicted (from right to left): Magnetica holding a compass, Stathmica representing the second Kepler´s law, Geometry with symbols of his first law, and Logarithmica (the invention of calculations with logarithms significantly helped Kepler). The penultimate goddess holding a telescope and the last one with the illuminated Earth in her hand remind Kepler´s inventions in optics.
An imperial eagle hovers above the roof, occasionally dropping a gold coin from his beak to astronomers. Two coins fall down to the pedestal, where Kepler is depicted in the left field, sitting at the table and calculating the tables by candlelight. In front of him on the table, there is the model of the roof of the temple: Kepler has crowned (with synthesis – i.e. with something like a roof – of then existing knowledge) the astronomy of his predecessors and described mathematically the order of the planets in the solar system.
Athanasii Kircheri Ars magna lucis et umbrae – The Great Art of Light and Shadow
published in Amsterdam in 1671, 850 pages
NK CR, shelf mark 15 A 57
The book is a work by Athanasius Kircher (1602-1680), a German scholar, polyhistor, Jesuit and author of more than forty voluminous works covering various fields.
In that work, a large number of topics is elaborated successively, including the theory of colors, the theory of radiation, refraction of light, parabolic mirrors, astrology, medicine, sundials, and astronomy. In many places, the text is supplemented by illustrative sketches.
It is interesting that the writing is dedicated to Jan Bedřich z Valdštejna (Jan Bedřich Graf von Waldstein), Bishop of Hradec Králové and later Archbishop of Prague.
In the centre of the engraved pre-title page, we can read the author´s name, the title of the writing and the name of the Emperor Ferdinand III Habsburg.
The God‘s authority is featured in the above part of engraving. The figure on the left side depicts the Sun and the figure on the right the Moon. On the Earth, the Moon shines by the reflected light of the Sun. Right below, sunlight breaks into the cave that represents a pinhole camera (camera obscura) – then a very popular device – a predecessor of a modern camera.