4to; 245x170 mm.; Pp. X, [2 blank]. Woodcut initial. Disbound, as issued, but with traces of having been in a binding for some time. Good copy.
Description of the Northern light observed in Rome in December 1737; the exceptional phenomenon was also reported by other scholars, including Giovanni Poleni and the astronomer Eustachio Zanotti. Baldini first hypothesizes that the phenomenon must have occurred at considerable heights in the atmosphere, as it was simultaneously visible in Italy, France, Denmark and Norway. He then tries to explain the phenomenon with the burning of vapors of sulfur and other easily combustible substances and adds that it manifests itself differently in the tropical and polar regions due to the different intensity of solar radiation and the consequent difference in the density of the air. The origin of the Northern light is quite different: “... At any given moment, the sun is ejecting charged particles from its corona, or upper atmosphere, creating the solar wind. When that wind slams into Earth's ionosphere, or upper atmosphere, the aurora is born. In the Northern Hemisphere, the phenomenon is called the northern lights (aurora borealis), while in the Southern Hemisphere, it's called the southern lights (aurora australis). ... The bright colors of the northern lights are dictated by the chemical composition of Earth's atmosphere.” G. Baldini, 1677-1764, cleric of the Order of the Clerics Regular of Somasca and theologian, wrote several works on numismatics and was also interested in physics. Moretti: “[his publication was] much appreciated in his time, despite the fact that the scientific explanation of the phenomenon is revealed today to be highly erroneous” (Moretti, translated).
Waldek and Dobrijevic: “Interestingly, the author reports two other occasions when he was able to observe the Northern Light, on 19 October 1726 in Tivoli and on 21 June 1730 in Rome and specifies that he could not find any record for the latter which took place in the period (May-July) when it is generally considered the phenomenon does not occur.”
Luigi Moretti, Baldini, Gianfrancesco, in DBI. In: Dizionario Biografico degli Italiani;
Stefanie Waldek, Daisy Dobrijevic, Northern lights (aurora borealis): What they are & how to see them
https://www.space.com/15139-northern-lights-auroras-earth-facts-sdcmp.html.