ORRERY. 
adoption in praétice. 
of the moo 
the Earth’s annual frame; but the g 
fome of thefe four orbits, no doubt, prefenteddifficulties more 
i than overcome in i 
contemplated, was not put in exe n. our opinion, 
the orrery would have been more complete if all the primary 
planets had been reprefented in motion, with f f 
rate magnifying powers, which was the plan propofed by 
the inventor of the machines which were immediately before 
defcribed. 
A L- } b ria + 
fALUCL davis P : : } s Pt 
worthy of public notice, we conceive that it will be 
rument-maker an acceptable fervice, if we 
1 bo Arh As 
a plate; with the extent 2° 47'.2 from Tab. V. in 
the dividers fet off both ways from each node, and the 
ftroke 0° 15! will be given in four places: again, with the 
extent 5° 34.9 fet off for the ftrokes 0° 30’, and in like 
manner for any other dividing ftroke that is required in any 
of the divided circles. 
Tase I.—Equation of the Sun’s Centre. 
Argument. Equation. rgument. Equation. 
Apogee 0° o! Perigee 0° Of 
ne ao <>) 4° 52! 0 Io 
Io Wt © 20 g 46 o 20 
Is 23 Oo 30 14 45 Oo 30 
20 Al o 40 Ig 51 Oo 40 
26 II o 50 25 9Q o 50 
31 57 Io 30 41 ro 
38 = 3 1 10 36 36 1 10 
44 42 i 20 43 2 1 20 
52 Io I 30 5° 17 I 30 
61 I 40 58 59 41 40 
73° «29 I 50 7t Wt I 50 
80 10 I 83 46 I 55 
gt 20 t 55% 88 40 1 55% 
n’s phafe are alfo propofed in the larger fe&tion, _ 
on’s arm in t i 
The little wheels for the parallelifm ‘Taste 1I.—The Sun's Declination with the correfpondent ° 
Diftances in the Ecliptic from Aries and Libra both 
ays. 
Argument Declination. 
a” 301.9 1° 
. ey, 2 
7 33 3 
‘ 10 52 4 
12 38.6 5 
15 12.9 6 
7 ao i 
20 24615 8 
23 «7.8 9 
25 50.9 Io 
28 8637.5 I 
at (27-1 12 
34 23-3 13 
37 24.2 14 
49 31-75 ) 
43 47.6 6 
47 13-9 17 
50 53-2 18 
64 7.8 21 
70 = «3 22 
78 50 a3 
go oO 234 
Tasie LI1I.—Reduétion of the Ecliptic to the Equator. 
Argument. Equation. 
o of °° 
3 2 o 95 
6 5 Oo 30 
9g 12 o 45 
12 25 -I oO 
15 46° I 15 
1g 25 I 30 
230 (24 I 45 
28 oO 2 0 
33. «21 2 15 
36 30 2 20 
40 2 25 
46 15 2 28 23".6 
52 20 2 25 
55 §1 2 20 
58 23 2 15 
64 0 2 0 
68 21 I 45 
72 13 I 30 
75 27 a) 
78 34 : 2 
81 33 ° 45 
84. 25 Oo 30 
87 13 Oo 15 
go oO on?) 
Tastz IV.—For the Moon’s mean Equation of the Centre. 
Argument. Equation. Argument Equation 
Apogee 0° o! Perigee 0° o! 
4° 51.6 o 30 4° «145 © 30 
9 44-7 1 0 8 31-3 Ir 0 
14 41.7 1 30 13 50.1 1 30 
19 44.1 2 0 17 15.2 2 0 
24 54-5 2 30 2% 48.6 2 30 
30 (16.3 re) 26 33.0 ) 
35 53:4 3 30 31 32.6 3 30 
