E 585 ] 
The inflamed Matter, in the greateft Part of its 
Extent, gave a free Paflage to the Rays of the Stars, 
even of the Third and Fourth Magnitude, fituate 
behind it. About the Fourth Hour of the Night, a 
very regular Arch of a parabolic Figure was feen to 
rife gently, to Two Degrees of rectangular Elevation, 
and to Twenty Degrees of horizontal Amplitude. 
This Phenomenon was feen all over Italy, as 
appears by feveral Accounts of it, though with fome 
Difagreement between them. 
But how bright foever and diftindt it appeared, yet 
its Caufe has been deemed by many to be very 
obfcure : For fome call it an Aurora Borealis, therein 
following the Opinion of Gajfendus , and deducing 
all the Appearances from the Laws of Ample Refrac- 
tion of the folarRays. Others think it an irradiation 
of fome luminous Comer, placed below our Ho- 
rizon. Others more politely fay, it was a new 
celeftial Body defcended from its upper Habitation 
down to us, and courteoully received by the Earth’s 
Vertex . Others, in Love with Authority, and French 
Names, have endeavoured to eftablith the Meteor 
as a Mixture of the Two Atmofpheres of the Sun 
and Earth ; therein tenacioufly adhering to the new 
Opinion of Monfieur de Mairan , of the Academy 
of Sciences atParis. In fine, others more accurately 
deduce the Whole from the Ample Firing of a bitu- 
minous and fulphureous Matter, upon account of 
irs very little fpecific Gravity, railed to the upper Parts 
of the Atmofphere, and there, by the Clafhing of 
contrary Winds, broken, comminuted, and at laft 
fet on Fire. This Opinion has been defended with 
ftrong Arguments, in the Petersburg Commentaries, 
