7o

Chapter

First.

C H R O N O L O G Y-.

ftar of the fourth magnitude, called y by Bayer; its longitude inthe end of the year 1689 was L. 24°. 25'. 27^ (^), and northlatitude -37°. 26'. 50": and the Colurus' JKquinoBiorum paflingthrough it cuts the ecliptic in 8. 4 0 . 56'. 40^ ( 9 ): and the fifthpart of the fum of the places in which thefe five Colures cutthe ecliptic, is 8.6°. 29^. i and therefore the great cir-

cle which in the primitive fphere, according to Eudoxus, and byconfequence in the time of the Argqnautic expedition, was theColurus JEquinotliorum paffing through the itars above-defcribed;did, in the end of the year 1689, cut the ecliptic in 6 1 . 6°. 29'15" (”): as nearly as we have been able to determine by the ob-fervations of the.ancients, which were but coarfe.

XXXIII. In the middle of Cancer is the South Afellus, a ftarof the fourth magnitude, called ,by Bayer $; its longitude inthe end of the year 1689 was S\. 4 0 . 23'. 40A In the neck ofHydrus, rightly delineated, is a ftar of the fourth magnitude*called <? by Bayer ; its longitude in the end of the year 1689 was£>h. 5 0 . 59'. 3". Between the poop and maft of the fhip Argo isa ftar of the third magnitude, called 1 by Bayer ; its longitudein the end of that year was Sh. 7°. 5'. 31". In Sagitta is a ftarof the ftxth magnitude, called g by Bayer; its longitude in theend of the fame year 1689 was RA. 6°. 29’. 53". In the middleof Capricorn is a ftar of the fiftli magnitude, called n by Bayer;its longitude in the end of the fame year was KU. 8°. 25'. 33" :and the fifth part of the fum of the three firft longitudes, and

■Let b, in fig. note 2, reprefent the piace of t Perfei.

° / y/

*Ihen b <3 ~ 34. 20 12

And ea b — 66 30 00

Therefore b.\ — 17 16 42

But yb — 53 35 30

Therefore VA zz 36 18 48

Raper’s copy has y . 6 18 48 written in his ownhand in the margin.

(*) Thib ftar does not appear in the Britannic. Catalogue : but in that of Heveiius its longi-tudo, at the end of the year 1660, is put down 8 - 24 0 . o'. 29''. Therefore-at the end of theyear 1689 its longitude iiiuft have been y . 24 0 . 24'. 29. In fig. note 2, let b denote the placeof this ltar.

Then

O £

II

•<5

/

26

//

5 °

And

BA^ “ 66

30

00

henec I find

ba n: jg

2 7

06

But

Tb ~ 54

-4

39

Therefore

Ta - 34

57

33

of