cording to the Cuftom of the other People who obferved the Moon's Motion; as Tacitus further confirms; For Tranfacting Business (fays he) they believe this juncture of time (the Sunset) the most auspicious: Neither do they reckon by Days as we do, but by Nights; and they fo order and appoint things, as if the Night Seemed to uber in the Day. And Cafar writes almoft the fame thing of the Gauls. This Custom the English obferve to this Day in their common Difcourfe, witness our Sennight, derived from Seven Night, and Fortnight from Fourteen Nights. But in Bohemia, and the adjacent Country of Poland, the ancient German Inftitution does plainly prevail; for there the Days run from Sunfet to Sunfet, at which time their Clocks Atrike 24. Civil Peri S.14. The Time of the Jewish Computation may be re- How to reduced to the Mathematical, which begins at Noon, if duce the you fubftract from the Jewish time given 18 Hours, Jewish and (for fo many Hours the Jewish Computation anticipates European the Mathematical, both in their Ecclefiaftical and Ciods of time vil Years) taking down or dividing an intire Day if to the Mathe fubftraction will not bear otherwife; after which bematical the Remainder will fhew the time fought. But if our which com Political Time, beginning from Midnight, was to be compared with the Mathematical, there will be no from need of Reduction, if the Hour given is in the After. Noon noon: But if in the Morning, add 12 to the given Hour, and fubftract 1 from the Number of Days; the Sum or Difference is the Mathematical time fought. mence CHA P. V. Of Months. RULES. 1. A Month is that part of Time by which we usually divide a Year into 12, and fometimes into 13 Parts. 2. Months are either Aftronomical or Civil. 3. Aftro logy of the Word Month. 3. Aftronomical are those that are measured by the motion of the Stars. 4. And because we generally have refpect to the Luminaries in ordering of 'em, fome we call Lunar and others Solar. 5. A Lunar Month is that space of time which is fpent in the Revolution of the Moon through its proper Orb ; er from Synod to Synod; or from the Appearance of the Moon after one Synod, to its appearance again after another. 6. Hence Nature feems to produce a threefold Lunar Month, that is, a Periodical, a Synodical and a Month of Illumination. 7. The Lunar Periodical Month is that space of time in which the Moon by her Motion returneth to the fame Place of her Orb from whence he fet out. 8. The Synodical is the space of time that runs from one Conjunction of the Luminaries to the next Conjunction following. 9. The Month of Illumination is that fpace of time intercepted betwixt the first appearance of the Moon after her Conjunction with the Sun, and the first ap pearance after the next Conjunction. 10. The Solar Month is that space of time wherein the Sun runs through one of the twelve Signs of the Zodiack by its proper Motion from West to Eaft. 11. A Civil Month is a System of Days which different Nations differently obferve in their Civil Affairs,purfuant to their voluntary Inftitutions. The Etymo. S. 1. AS to the Etymology of the Word it is obfervable that in almost every Language it is derived from the Moon, as among the Hebrews denot⚫ eth as well the Moon as a Month. And among the Greeks uu, has a plain relation to unr, i. e. the Moon. Cicero de Nat. Deor. 2. derives the Latin Word Menfis from the Courfes of the Moon, for that they make Menfa Spatia, or measure out Spaces; which the German Word Monet, and our Word Month both derived from the Moon, do likewife denote. Theancient form of Months. §. 2. From whence it appears that the Hebrews, Greeks, Latins, and Germans obferved the Courfe of the Moon: For although Arguments deduced from E tymologies tymologies of Words are but of little force; yet they are of weight when joyned with other Proofs, efpe cially if we take notice of the nervousness of the Hebrew Language and its Harmonical confent with those others mentioned before; whence Fulian in that Hymn dedicated to the Sun, the King of all things, fays, the Months are numbred from the Moon, by all other Mortals, befides Us and the Egyptians whe compute our Days of the Year by the Mation of the Sun. Tho' after all the Lunar Manth was not unknowa to the Romans, though the Apoftate excepts them, for the time of Parturition, which with them was the tenth Month, feems to run upon a Lunar Calcylation: in which Senfe thefe Lines of Quid are to be understood. Annus erat decimum cum Luna receperat Orbem. S. 3. As to the Myftick Months confifting of 49 or of Mystice 7 times 7 Days; though there can be no Nation fo Months. barbarous as wholly to lay afide an Analogy with the Motion of the Heavenly Bodies, in adjusting the Pe riods of Time; yet the Author of the Mystick Chro nology (pares not to charge the Jews themselves with that neglect. Befides that his Affertions are given in without Proof, or rather are fictitious, they are likewife clogg'd with maný Abfurdities: For nothing can be fo unreasonable, as that God, who created the Laminaries for fet-times, Years and Months,fhould reach aPeaple peculiar to himself a method that departs from that Standard. Add to this that the forementioned Word n derived from the Moon, is of an ancient Date. Befides, who knows not that the Jews in the chief Feaft of the Paffover obferve the Moon, and always celebrate the Feaft at the Full Moon, and on the 15 day of the first Month. But fuppofe the Jews had their Myftical Months confifting of 49 Days; this Number of Days having no agreeableness with the Lunar Motion, instead of full Moon, you will have nothing on the fet Day but meer Darkness.Further,the Writers of the Old Tefta of a Peri odical Month. dical Month. Teftament, who doubtlefs were Sacred and holy Perfons, in fpeaking of Sacred and Divine things, have made mention of the 8th and other Months beyond the 7th. In fine, if the Myftical Nature of the Septenary Number muft outweigh all the Traditions and Opínions of Men, why did not this Mystery Expounder likewife furmife the fame thing of a Day of 7 Hours, and of Hours of 7 Minutes, and fo on? S. 4. We here again mention the Periodical Month in regard that it may be of ufe to confider it narrowly whence Kepler calleth the Periodical Month the Phyficians Critical Month. As to its quantity it is indeed unequal, and can be found no otherwise than by Aftronomical Calculation, by which it will appear that its mean Motion is performed in 27 Days, 7 Hours, 43 Minutes, 5 Seconds. The diffeS. 5. The difference between a Periodical and a Syrence of a nodical Month, is this: The firft is called Periodical Periodical only in refpect of the Moons Orbit, but the Synoand Syno- dical is fo called in refpect of its Conjunction with the other Luminaries. Now after the time of its Conjunction the Sun does not continue in the fame place of the Zodiack, but moves forwards towards the East; upon which it falls out that the Moon finishing its Courfe does not find the Sun again in the fame point where it left him; he being removed almost a whole Sign from his former place. So that to overtake the Sun again, it plainly appears that a certain space of time is requifite, befides the Periodical,which makes up the Synodical Month. of a Syno dical Month. §. 6. But as to the true quantity of the Synodical Month, we are to gather it from Aftronomers, who ftudy its Motion; as Chronologers do the time in which the Motion is made; however fince a Synodical Month is apparently unequal, we fhall content our felves with the enumerating from feveral Authors their opi nions of its mean Motion, as they call it; among which we take Tycho Brahe's to be the most Genuine : They are thefe; [ 1. Cleo. S. 7. The quantity of a Synodical Month is not Synodical the fame at all times; for in the Summer Solstice, when not always the Sun feems to move floweft the Synodic Month ap- the fame. peareth lefs, being about 29 Days, 6 Hours, and 42 Mi nutes: But in the Winter, when the Suns. Motion feems fafter, the Moon does not fetch up the Sun fo foon: for which reafon the Synodical Month then feems greater, viz. 29 Days, 19 Hours, and 37 Minutes, as fome Aftronomers do obferve. So that what has been faid in the preceding Paragraph about a Synodical Month, is to be understood as to the mean Motion. §. 8. Some Months are called Pleni and others Ca- of the vi; the Pleni are thofe that confift of 30 Days, the MonthscalCavi of 29, and thefe two in the Lunar or Lunar- led Pleni Solar Year are placed alternately, by reafon of the and Cavi. Appendage of 12 Hours, which being omitted in one Month, and doubled in another, make 24: For which reafon they can be no longer neglected, but are to be be compenfated by the 30th Day, over and above the 29th. S. 9. Some by the Month of Illumination under- of the ftand that space of time which is intercepted between Months of the first and laft appearance of the Moon, which ac- Illumina ception of the thing, though it be otherwife tolerable, tion. yet fince no fuch Month was ever used by any fort of People we know of, it may juftly give place to the defcription we gave in our Rules. §. io The Lunar Month of Illumination is not of of the i any certain determined quantity, for the Moon appears quantity of fometimes fooner, fometimes later after the Conjuncti- the fame. on; for which diverfity the Aftronomers give you fe |