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knowledges their Motions are regulated by Lawsthen unknown; and prophesies far from falsely,that the diligence and experience of some futureAge would discover these Mysteries ; and wonderthat the Antients were ignorant of them: Afterthat some Interpreter of Nature should demonstratein what Regions of the Firmament Comets move,shewing both their Magnitudes and Qualities. Yetthe greatest part of Astronomers have thought dif-ferently from Seneca ; and he himself has not trans-mitted to us the Phænomena of the Motions onwhich his Opinion is grounded, nor the Time whenhe obferv’d them, all which would have been ofUse to the Moderns to determine this Controversy.

And after searching into many Histories of Co-mets, I find none than can be of any Use in thisaftair before the year of Christ 1337* when A 7 -cephoras Gregoras , an Historian and Astronomer atConjlantinople, describes to us accurately enough theTract of a Comet among the fixt Stars, but he isvery remiss as to the time of its appearance, onWhich account it merits a place in the Cataloguewe shall give hereafter, no otherwise than that it isvery probable it appeared about 400 Years ago.

After this, in the year 1742, Regiomontanus *observed a Comet, the swiftest and nearest the Earthof any ; which tho’ large in bulk, and having aterrible Tail, in one day passed thro' 40 degreesof a great Circle of the Heavens; and this is thefirst Comet concerning which proper Observations

* Regiomontanus , a German Astronomer; he abridged Ptolemy'sAlmageftum , he found many material Errors in the Translationof it, by George of Trebizond, and being made Archbilhop ofRaiisoon, and coming to Rome to reform the Calendar, he waskilled by George of Jrebizcnde's Son, Anno 1476, others fay hedied of the Plague, aged 40.

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