(%<#> y

Ciear p^rts and tbe Spots, so far as to t>e able jto discern th'etn ali. TheSbadows also of ali the Cayities of, the Mopn.seem to be stronger, than theyvroald.be, if. there were .a fecond Light. For although afar off the Sha-dows ofour Bodies, environcd wkh Light, scera to us almoft Dark, yct theydo not so appear, so mucb .as the Shadows of the Moon do ; and thole that.ire upon tbe Edge of the Section, stiould not appear in the like Männer. Bur1 will determine nothing of any of thefc things.

~fo find tbe ?»--y*tUx os tbeMoon .....n. ?. f.151.

1

XXXVIIi. At ccrtain times agrecd on by two Ohscrvators, raaking use ofTelefcopes Large, Good, and well Fitted for this Purpose, by a measoringRod, placcd within the Eye-Glafs at a convenient Distance, that it may be di-stsoctly seen, and ferve for Measoring small Distances by Minutes and Seconds,

( which is easie cnough in large Telefcopes) Lee each of iuch Obfervators,thus furnifht, Obserye thp .vifible Way of the Moon amqng the Fixt Stars,

( by takingher exact Distance fromany Fixt Star, that lies so or very near herWay, together with the exact time of her so Appearing) and.the then ApparentDiameter of her Disk j continuing thele Observations every time for two or threeHours, that so if poflible, two exact. Observations of her Apparent Place amongthe Fixt Stars, besog mäde, at two Places thus distant in Latitude, and asnear asmay be under the sirne. Meridian, by thefe Qbservations, coneurrsog at the famc time*her true ’and exact Distamq? may be hence collected, .not only for that time, butat all other times, byany üngle Observator’s Viewsog her with a Teseseopc, andmeasoring exactly her Apparent Diameter. It were likewise defjrable, that as of-ten as there happens any confiderable Eclipsi; of the Sun, that this .also migbt beobserv’d by them» noting therein the exact Measore of tl^e Greatest Obfcurationcompared^ith the then Apparent Diameter, of his Disk. For by this.means, as-ter, the Distance .of the Moon hathbeen exactly stund, .the Distance of the Sunwill eafily be deduced.

As for the Time littest for maksog Observations of the Moon, That will be.when. Ihe is about a Qyarter or lomewhat lest Illuminated, because theil herLight is not so bright, but that with a good Tekseppe, Ihe may be Observ'd topaß dose by, and lbtneümes over several Fixt Stars, which is about four or ht»eDays beforcor aster her-Change ; Or elfe aS any, pther tinx), when the MoonBastes near or over some of the Bigger fort of Fixt Stars, soch as of the First andSecond Magnitude ; which may be eafily Calculated and foreseen: Or best of alL,whenjthere is any Total Eclipfe of the Moon ; for theil the smallelLTelefcopicalStars may be fcenclose adjoynsogto the. very Body qfrhe Moon.

«a.aIuW for . XXXIX. 1. Eclipses of the Moon .are observed for two Principal Ertds ; OneEAstronomical, that by comparing Observations with Calculations, the Theory of;r.ooU. \\. 22. ehe Moon’s Motion may be Persected, and the Tables thereof Reformed : the?- other Geographical, that by comparing among themselves the Observations of the

sime Ecliptick Phases, made in divers Places, the Difference of Meridians orLongitudes of thofc Places may be diseerped.

The Knowledge of the Eclipse’s Quantity and Duration, thp Shadow’s Curvi-ty . andlnclination, sie. conduce. only to the formet, of these Ends. The exactTime of the Beginning, Middle, and End of the Eclipses, as also in Total Ones,iheJJpgsoning and End of Total Darkneß, is usetul for both of them. But